LK NEHR Sri Lanka Patient Summary (IPS based) Implementation Guide
0.1.0 - STU1 Sri Lanka flag

LK NEHR Sri Lanka Patient Summary (IPS based) Implementation Guide, published by Ministry of Health, Sri Lanka. This guide is not an authorized publication; it is the continuous build for version 0.1.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/lk-gov-health-hiu/lk-nehr-fhir-ips/ and changes regularly. See the Directory of published versions

Resource Profile: FastingBloodSugar - Detailed Descriptions

Active as of 2024-11-14

Definitions for the fasting-blood-sugar resource profile.

Guidance on how to interpret the contents of this table can be found here

0. Observation
2. Observation.category
Control0..1
4. Observation.category.coding
6. Observation.category.coding.system
Pattern Valuehttp://terminology.hl7.org/CodeSystem/observation-category
8. Observation.category.coding.code
Pattern Valuelaboratory
10. Observation.code
Pattern Value{
  "coding" : [{
    "system" : "http://loinc.org",
    "code" : "76629-5"
  }]
}
12. Observation.code.text
Pattern ValueFasting glucose
14. Observation.subject
TypeReference(Patient)
16. Observation.encounter
TypeReference(Target Facility Encounter)
18. Observation.performer
TypeReference(Practitioner, Organization)
20. Observation.value[x]:valueQuantity
Slice NamevalueQuantity
TypeQuantity(Quantity (IPS))
[x] NoteSeeChoice of Data Typesfor further information about how to use [x]
22. Observation.value[x]:valueQuantity.value
Control1..?
24. Observation.value[x]:valueQuantity.unit
Pattern Valuemmol/L
26. Observation.value[x]:valueQuantity.code
Pattern Valuemmol/L
28. Observation.interpretation
Definition

reason(s) why this should be supported.

Must Supporttrue
30. Observation.device
Control1..?
TypeReference(Device Information)
32. Observation.referenceRange
Definition

reason(s) why this should be supported.

Must Supporttrue

Guidance on how to interpret the contents of this table can be found here

0. Observation
Definition

This observation may represent the result of a simple laboratory test such as hematocrit or it may group the set of results produced by a multi-test study or panel such as a complete blood count, a dynamic function test, a urine specimen study. In the latter case, the observation carries the overall conclusion of the study and references the atomic results of the study as "has-member" child observations


Measurements and simple assertions made about a patient, device or other subject.

ShortLaboratory result for a simple test or for a panel/studyMeasurements and simple assertions
Comments

Represents either a lab simple observation or the group of observations produced by a laboratory study.


Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc.

Control0..*
Is Modifierfalse
Summaryfalse
Alternate NamesVital Signs, Measurement, Results, Tests
Invariantsdom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
obs-7: If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty())
ips-2: if no "hasMember" element is present then Observation must have a" value" (value.exists() or hasMember.exists())
obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
obs-7: If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty())
2. Observation.implicitRules
Definition

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

ShortA set of rules under which this content was created
Comments

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

Control0..1
Typeuri
Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. Observation.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored
Comments

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summaryfalse
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
6. Observation.status
Definition

The status of the result value.

Shortregistered | preliminary | final | amended +
Comments

This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.

Control1..1
BindingThe codes SHALL be taken from ObservationStatushttp://hl7.org/fhir/ValueSet/observation-status|4.0.1
(required to http://hl7.org/fhir/ValueSet/observation-status|4.0.1)

Codes providing the status of an observation.

Typecode
Is Modifiertrue because This element is labeled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Requirements

Need to track the status of individual results. Some results are finalized before the whole report is finalized.

Fixed Valuefinal
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. Observation.category
Definition

A code that classifies the general type of observation being made. In this profile, fixed to "laboratory".


A code that classifies the general type of observation being made.

ShortConcept - reference to a terminology or just textClassification of type of observation
Comments

"laboratory" includes laboratory medicine and pathology


In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set.

Control10..1*
This element is affected by the following invariants: ele-1
BindingThe codes SHOULD be taken from ObservationCategoryCodeshttp://hl7.org/fhir/ValueSet/observation-category
(preferred to http://hl7.org/fhir/ValueSet/observation-category)

Codes for high level observation categories.

TypeCodeableConcept(Codeable Concept (IPS))
Is Modifierfalse
Requirements

Used for filtering what observations are retrieved and displayed.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
SlicingThis element introduces a set of slices on Observation.category. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • pattern @ $this
  • 10. Observation.category.coding
    Definition

    A reference to a code defined by a terminology system.

    ShortA reference to a code defined by a terminology systemCode defined by a terminology system
    Comments

    Codes may be defined very casually in enumerations or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information.


    Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.

    Control0..*
    This element is affected by the following invariants: ele-1
    TypeCoding(Coding with translations)
    Is Modifierfalse
    Must Supporttrue
    Requirements

    Allows for alternative encodings within a code system, and translations to other code systems.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    12. Observation.category.coding.system
    Definition

    The identification of the code system that defines the meaning of the symbol in the code.

    ShortIdentity of the terminology system
    Comments

    The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously.

    Control0..1
    Typeuri
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    Need to be unambiguous about the source of the definition of the symbol.

    Pattern Valuehttp://terminology.hl7.org/CodeSystem/observation-category
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    14. Observation.category.coding.code
    Definition

    A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).

    ShortSymbol in syntax defined by the system
    Control0..1
    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    Need to refer to a particular code in the system.

    Pattern Valuelaboratory
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    16. Observation.category.coding.display
    Definition

    A representation of the meaning of the code in the system, following the rules of the system.

    ShortRepresentation defined by the system
    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    Need to be able to carry a human-readable meaning of the code for readers that do not know the system.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    18. Observation.category.coding.display.extension:translation
    Slice Nametranslation
    Definition

    Language translation from base language of resource to another language.

    ShortLanguage Translation (Localization)
    Control0..*
    This element is affected by the following invariants: ele-1
    TypeExtension(Translation) (Complex Extension)
    Is Modifierfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    20. Observation.category.text
    Definition

    A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.

    ShortPlain text representation of the concept
    Comments

    Very often the text is the same as a displayName of one of the codings.

    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    22. Observation.category:laboratory
    Slice Namelaboratory
    Definition

    A concept that may be defined by a formal reference to a terminology or ontology or may be provided by text.


    A code that classifies the general type of observation being made.

    ShortConcept - reference to a terminology or just textClassification of type of observation
    Comments

    Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination.


    In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set.

    Control10..1*
    This element is affected by the following invariants: ele-1
    BindingThe codes SHOULD be taken from ObservationCategoryCodeshttp://hl7.org/fhir/ValueSet/observation-category
    (preferred to http://hl7.org/fhir/ValueSet/observation-category)

    Codes for high level observation categories.

    TypeCodeableConcept(Codeable Concept (IPS))
    Is Modifierfalse
    Must Supporttrue
    Requirements

    Used for filtering what observations are retrieved and displayed.

    Pattern Value{
      "coding" : [{
        "system" : "http://terminology.hl7.org/CodeSystem/observation-category",
        "code" : "laboratory"
      }]
    }
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    24. Observation.code
    Definition

    Describes what was observed. Sometimes this is called the observation "name". In this profile this code represents either a simple laboratory test or a laboratory study with multiple child observations


    Describes what was observed. Sometimes this is called the observation "name".

    ShortConcept - reference to a terminology or just textType of observation (code / type)
    Comments

    In the context of this Observation-laboratory-uv-ips profile, when the observation plays the role of a grouper of member sub-observations, the code represent the group (for instance a panel code). In case no code is available, at least a text shall be provided.


    All code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation.

    Control1..1
    This element is affected by the following invariants: ele-1
    BindingThe codes SHOULD be taken from For example codes, see Results Laboratory Observation - IPShttp://hl7.org/fhir/ValueSet/observation-codes
    (preferred to http://hl7.org/fhir/uv/ips/ValueSet/results-laboratory-observations-uv-ips)
    TypeCodeableConcept(Codeable Concept (IPS))
    Is Modifierfalse
    Must Supporttrue
    Requirements

    Knowing what kind of observation is being made is essential to understanding the observation.

    Alternate NamesName
    Pattern Value{
      "coding" : [{
        "system" : "http://loinc.org",
        "code" : "76629-5"
      }]
    }
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    26. Observation.code.coding
    Definition

    A reference to a code defined by a terminology system.

    ShortA reference to a code defined by a terminology systemCode defined by a terminology system
    Comments

    Codes may be defined very casually in enumerations or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information.


    Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.

    Control0..*
    This element is affected by the following invariants: ele-1
    TypeCoding(Coding with translations)
    Is Modifierfalse
    Must Supporttrue
    Requirements

    Allows for alternative encodings within a code system, and translations to other code systems.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    28. Observation.code.text
    Definition

    A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.

    ShortPlain text representation of the concept
    Comments

    Very often the text is the same as a displayName of one of the codings.

    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

    Pattern ValueFasting glucose
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    30. Observation.subject
    Definition

    The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the focus element or the code itself specifies the actual focus of the observation.

    ShortWho and/or what the observation is about
    Comments

    One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated.

    Control10..1
    TypeReference(Patient, Patient, Group, Device, Location)
    Is Modifierfalse
    Must Supporttrue
    Summarytrue
    Requirements

    Observations have no value if you don't know who or what they're about.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    32. Observation.subject.reference
    Definition

    A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

    ShortLiteral reference, Relative, internal or absolute URL
    Comments

    Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

    Control10..1
    This element is affected by the following invariants: ref-1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    34. Observation.encounter
    Definition

    The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made.

    ShortHealthcare event during which this observation is made
    Comments

    This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests).

    Control0..1
    TypeReference(Target Facility Encounter, Encounter)
    Is Modifierfalse
    Summarytrue
    Requirements

    For some observations it may be important to know the link between an observation and a particular encounter.

    Alternate NamesContext
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    36. Observation.effective[x]
    Definition

    The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself.

    ShortClinically relevant time/time-period for observation
    Comments

    At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the Timing datatype which allow the measurement to be tied to regular life events.

    Control10..1
    TypeChoice of: dateTime, Period, Timing, instant
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Must Support TypesNo must-support rules about the choice of types/profiles
    Summarytrue
    Requirements

    Knowing when an observation was deemed true is important to its relevance as well as determining trends.

    Alternate NamesOccurrence
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    38. Observation.effective[x].extension:data-absent-reason
    Slice Namedata-absent-reason
    Definition

    Provides a reason why the effectiveTime is missing.

    Shorteffective[x] absence reason
    Control0..1
    TypeExtension(Data Absent Reason) (Extension Type: code)
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    40. Observation.performer
    Definition

    Who was responsible for asserting the observed value as "true".

    ShortWho is responsible for the observation
    Control10..*
    TypeReference(Practitioner, Organization, Practitioner, PractitionerRole, Organization, CareTeam, Patient, RelatedPerson)
    Is Modifierfalse
    Must Supporttrue
    Must Support TypesNo must-support rules about the choice of types/profiles
    Summarytrue
    Requirements

    May give a degree of confidence in the observation and also indicates where follow-up questions should be directed.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    42. Observation.value[x]
    Definition

    The information determined as a result of making the observation, if the information has a simple value.

    ShortActual result
    Comments

    An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

    Control0..1
    This element is affected by the following invariants: obs-7
    TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Must Support TypesNo must-support rules about the choice of types/profiles
    Summarytrue
    Requirements

    An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    SlicingThis element introduces a set of slices on Observation.value[x]. The slices areUnordered and Closed, and can be differentiated using the following discriminators:
    • type @ $this
    • 44. Observation.value[x]:valueQuantity
      Slice NamevalueQuantity
      Definition

      A measured amount (or an amount that can potentially be measured). Note that measured amounts include amounts that are not precisely quantified, including amounts involving arbitrary units and floating currencies. This profile imposes that the code system for units be UCUM.


      The information determined as a result of making the observation, if the information has a simple value.

      ShortA measured amount using UCUMActual result
      Comments

      The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator.


      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: ele-1, obs-7
      TypeQuantity(Quantity (IPS)), dateTime, boolean, string, SampledData, Period, Ratio, integer, time, Range, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Must Supporttrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      qty-3: If a code for the unit is present, the system SHALL also be present (code.empty() or system.exists())
      46. Observation.value[x]:valueQuantity.value
      Definition

      The value of the measured amount. The value includes an implicit precision in the presentation of the value.

      ShortNumerical value (with implicit precision)
      Comments

      The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books).

      Control10..1
      Typedecimal
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Precision is handled implicitly in almost all cases of measurement.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      48. Observation.value[x]:valueQuantity.comparator
      Definition

      How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value.

      Short< | <= | >= | > - how to understand the value
      Control0..1
      BindingThe codes SHALL be taken from QuantityComparatorhttp://hl7.org/fhir/ValueSet/quantity-comparator|4.0.1
      (required to http://hl7.org/fhir/ValueSet/quantity-comparator|4.0.1)

      How the Quantity should be understood and represented.

      Typecode
      Is Modifiertrue because This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.

      Meaning if MissingIf there is no comparator, then there is no modification of the value
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      50. Observation.value[x]:valueQuantity.unit
      Definition

      A human-readable form of the unit.

      ShortUnit representation
      Control0..1
      Typestring
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.

      Pattern Valuemmol/L
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      52. Observation.value[x]:valueQuantity.system
      Definition

      The identification of the system that provides the coded form of the unit.

      ShortUCUM system for unitsSystem that defines coded unit form
      Control10..1
      This element is affected by the following invariants: qty-3
      Typeuri
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Requirements

      Need to know the system that defines the coded form of the unit.

      Fixed Valuehttp://unitsofmeasure.org
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      54. Observation.value[x]:valueQuantity.code
      Definition

      A computer processable form of the unit in some unit representation system.

      ShortCoded form of the unit
      Comments

      The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system.

      Control10..1
      Typecode
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Requirements

      Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest.

      Pattern Valuemmol/L
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      56. Observation.value[x]:valueString
      Slice NamevalueString
      Definition

      The information determined as a result of making the observation, if the information has a simple value.

      ShortActual result
      Comments

      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: obs-7
      Typestring, dateTime, boolean, SampledData, Quantity, Period, Ratio, integer, time, Range, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      58. Observation.value[x]:valueRange
      Slice NamevalueRange
      Definition

      A set of ordered Quantities defined by a low and high limit.


      The information determined as a result of making the observation, if the information has a simple value.

      ShortSet of values bounded by low and highActual result
      Comments

      The stated low and high value are assumed to have arbitrarily high precision when it comes to determining which values are in the range. I.e. 1.99 is not in the range 2 -> 3.


      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: ele-1, obs-7
      TypeRange(Range (IPS)), dateTime, boolean, string, SampledData, Quantity, Period, Ratio, integer, time, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Must Supporttrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      rng-2: If present, low SHALL have a lower value than high (low.empty() or high.empty() or (low <= high))
      60. Observation.value[x]:valueRatio
      Slice NamevalueRatio
      Definition

      A relationship of two Quantity values - expressed as a numerator and a denominator.


      The information determined as a result of making the observation, if the information has a simple value.

      ShortA ratio of two Quantity values - a numerator and a denominatorActual result
      Comments

      The Ratio datatype should only be used to express a relationship of two numbers if the relationship cannot be suitably expressed using a Quantity and a common unit. Where the denominator value is known to be fixed to "1", Quantity should be used instead of Ratio.


      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: ele-1, obs-7
      TypeRatio(Ratio (IPS)), dateTime, boolean, string, SampledData, Quantity, Period, integer, time, Range, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Must Supporttrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      rat-1: Numerator and denominator SHALL both be present, or both are absent. If both are absent, there SHALL be some extension present ((numerator.empty() xor denominator.exists()) and (numerator.exists() or extension.exists()))
      62. Observation.value[x]:valueTime
      Slice NamevalueTime
      Definition

      The information determined as a result of making the observation, if the information has a simple value.

      ShortActual result
      Comments

      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: obs-7
      Typetime, dateTime, boolean, string, SampledData, Quantity, Period, Ratio, integer, Range, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      64. Observation.value[x]:valueDateTime
      Slice NamevalueDateTime
      Definition

      The information determined as a result of making the observation, if the information has a simple value.

      ShortActual result
      Comments

      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: obs-7
      TypedateTime, boolean, string, SampledData, Quantity, Period, Ratio, integer, time, Range, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      66. Observation.value[x]:valuePeriod
      Slice NamevaluePeriod
      Definition

      The information determined as a result of making the observation, if the information has a simple value.

      ShortActual result
      Comments

      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: obs-7
      TypePeriod, dateTime, boolean, string, SampledData, Quantity, Ratio, integer, time, Range, CodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Must Supporttrue
      Summarytrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      68. Observation.value[x]:valueCodeableConcept
      Slice NamevalueCodeableConcept
      Definition

      A concept that may be defined by a formal reference to a terminology or ontology or may be provided by text.


      The information determined as a result of making the observation, if the information has a simple value.

      ShortConcept - reference to a terminology or just textActual result
      Comments

      Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination.


      An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

      Control0..1
      This element is affected by the following invariants: ele-1, obs-7
      BindingThe codes SHOULD be taken from For codes, see Results Coded Values Laboratory - IPS
      (preferred to http://hl7.org/fhir/uv/ips/ValueSet/results-coded-values-laboratory-uv-ips)
      TypeCodeableConcept(Codeable Concept (IPS)), dateTime, boolean, string, SampledData, Quantity, Period, Ratio, integer, time, Range
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Is Modifierfalse
      Must Supporttrue
      Requirements

      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      70. Observation.interpretation
      Definition

      reason(s) why this should be supported.


      A categorical assessment of an observation value. For example, high, low, normal.

      ShortConcept - reference to a terminology or just textHigh, low, normal, etc.
      Comments

      Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination.


      Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result.

      Control0..*
      This element is affected by the following invariants: ele-1
      BindingUnless not suitable, these codes SHALL be taken from ObservationInterpretationCodeshttp://hl7.org/fhir/ValueSet/observation-interpretation
      (extensible to http://hl7.org/fhir/ValueSet/observation-interpretation)

      Codes identifying interpretations of observations.

      TypeCodeableConcept(Codeable Concept (IPS))
      Is Modifierfalse
      Must Supporttrue
      Requirements

      For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result.

      Alternate NamesAbnormal Flag
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      72. Observation.device
      Definition

      The device used to generate the observation data.

      Short(Measurement) Device
      Comments

      Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant.

      Control10..1
      TypeReference(Device Information, Device, DeviceMetric)
      Is Modifierfalse
      Summaryfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      74. Observation.referenceRange
      Definition

      reason(s) why this should be supported.


      Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two referenceRange elements would be used.

      ShortProvides guide for interpretation
      Comments

      Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties.

      Control0..*
      TypeBackboneElement
      Is Modifierfalse
      Must Supporttrue
      Summaryfalse
      Requirements

      Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      obs-3: Must have at least a low or a high or text (low.exists() or high.exists() or text.exists())
      obs-3: Must have at least a low or a high or text (low.exists() or high.exists() or text.exists())
      76. Observation.referenceRange.modifierExtension
      Definition

      May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

      Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

      ShortExtensions that cannot be ignored even if unrecognized
      Comments

      There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

      Control0..*
      TypeExtension
      Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
      Summarytrue
      Requirements

      Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

      Alternate Namesextensions, user content, modifiers
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      78. Observation.component
      Definition

      Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations.

      ShortComponent results
      Comments

      For a discussion on the ways Observations can be assembled in groups together see Notes below.

      Control0..*
      TypeBackboneElement
      Is Modifierfalse
      Must Supporttrue
      Summarytrue
      Requirements

      Component observations share the same attributes in the Observation resource as the primary observation and are always treated a part of a single observation (they are not separable). However, the reference range for the primary observation value is not inherited by the component values and is required when appropriate for each component observation.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      80. Observation.component.modifierExtension
      Definition

      May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

      Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

      ShortExtensions that cannot be ignored even if unrecognized
      Comments

      There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

      Control0..*
      TypeExtension
      Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
      Summarytrue
      Requirements

      Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

      Alternate Namesextensions, user content, modifiers
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      82. Observation.component.code
      Definition

      Describes what was observed. Sometimes this is called the observation "code".

      ShortType of component observation (code / type)
      Comments

      All code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation.

      Control1..1
      BindingFor example codes, see LOINCCodeshttp://hl7.org/fhir/ValueSet/observation-codes
      (example to http://hl7.org/fhir/ValueSet/observation-codes)

      Codes identifying names of simple observations.

      TypeCodeableConcept
      Is Modifierfalse
      Summarytrue
      Requirements

      Knowing what kind of observation is being made is essential to understanding the observation.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

      Guidance on how to interpret the contents of this table can be found here

      0. Observation
      Definition

      This observation may represent the result of a simple laboratory test such as hematocrit or it may group the set of results produced by a multi-test study or panel such as a complete blood count, a dynamic function test, a urine specimen study. In the latter case, the observation carries the overall conclusion of the study and references the atomic results of the study as "has-member" child observations

      ShortLaboratory result for a simple test or for a panel/study
      Comments

      Represents either a lab simple observation or the group of observations produced by a laboratory study.

      Control0..*
      Is Modifierfalse
      Summaryfalse
      Alternate NamesVital Signs, Measurement, Results, Tests
      Invariantsdom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
      dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
      dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
      dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
      dom-6: A resource should have narrative for robust management (text.`div`.exists())
      obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
      obs-7: If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty())
      ips-2: if no "hasMember" element is present then Observation must have a" value" (value.exists() or hasMember.exists())
      2. Observation.id
      Definition

      The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

      ShortLogical id of this artifact
      Comments

      The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

      Control0..1
      Typeid
      Is Modifierfalse
      Summarytrue
      4. Observation.meta
      Definition

      The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.

      ShortMetadata about the resource
      Control0..1
      TypeMeta
      Is Modifierfalse
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      6. Observation.implicitRules
      Definition

      A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

      ShortA set of rules under which this content was created
      Comments

      Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

      Control0..1
      Typeuri
      Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      8. Observation.language
      Definition

      The base language in which the resource is written.

      ShortLanguage of the resource content
      Comments

      Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource. Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).

      Control0..1
      BindingThe codes SHOULD be taken from CommonLanguages
      (preferred to http://hl7.org/fhir/ValueSet/languages)

      A human language.

      Additional BindingsPurpose
      AllLanguagesMax Binding
      Typecode
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summaryfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      10. Observation.text
      Definition

      A human-readable narrative that contains a summary of the resource and can be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.

      ShortText summary of the resource, for human interpretation
      Comments

      Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.

      Control0..1
      TypeNarrative
      Is Modifierfalse
      Summaryfalse
      Alternate Namesnarrative, html, xhtml, display
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      12. Observation.contained
      Definition

      These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.

      ShortContained, inline Resources
      Comments

      This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.

      Control0..*
      TypeResource
      Is Modifierfalse
      Summaryfalse
      Alternate Namesinline resources, anonymous resources, contained resources
      14. Observation.extension
      Definition

      May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

      ShortAdditional content defined by implementations
      Comments

      There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

      Control0..*
      TypeExtension
      Is Modifierfalse
      Summaryfalse
      Alternate Namesextensions, user content
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      16. Observation.modifierExtension
      Definition

      May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

      Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

      ShortExtensions that cannot be ignored
      Comments

      There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

      Control0..*
      TypeExtension
      Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
      Summaryfalse
      Requirements

      Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

      Alternate Namesextensions, user content
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      18. Observation.identifier
      Definition

      A unique identifier assigned to this observation.

      ShortBusiness Identifier for observation
      NoteThis is a business identifier, not a resource identifier (see discussion)
      Control0..*
      TypeIdentifier
      Is Modifierfalse
      Summarytrue
      Requirements

      Allows observations to be distinguished and referenced.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      20. Observation.basedOn
      Definition

      A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed.

      ShortFulfills plan, proposal or order
      Control0..*
      TypeReference(CarePlan, DeviceRequest, ImmunizationRecommendation, MedicationRequest, NutritionOrder, ServiceRequest)
      Is Modifierfalse
      Summarytrue
      Requirements

      Allows tracing of authorization for the event and tracking whether proposals/recommendations were acted upon.

      Alternate NamesFulfills
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      22. Observation.partOf
      Definition

      A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure.

      ShortPart of referenced event
      Comments

      To link an Observation to an Encounter use encounter. See the Notes below for guidance on referencing another Observation.

      Control0..*
      TypeReference(MedicationAdministration, MedicationDispense, MedicationStatement, Procedure, Immunization, ImagingStudy)
      Is Modifierfalse
      Summarytrue
      Alternate NamesContainer
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      24. Observation.status
      Definition

      The status of the result value.

      Shortregistered | preliminary | final | amended +
      Comments

      This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.

      Control1..1
      BindingThe codes SHALL be taken from ObservationStatus
      (required to http://hl7.org/fhir/ValueSet/observation-status|4.0.1)

      Codes providing the status of an observation.

      Typecode
      Is Modifiertrue because This element is labeled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Need to track the status of individual results. Some results are finalized before the whole report is finalized.

      Fixed Valuefinal
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      26. Observation.category
      Definition

      A code that classifies the general type of observation being made. In this profile, fixed to "laboratory".

      ShortConcept - reference to a terminology or just text
      Comments

      "laboratory" includes laboratory medicine and pathology

      Control1..1
      This element is affected by the following invariants: ele-1
      BindingThe codes SHOULD be taken from ObservationCategoryCodes
      (preferred to http://hl7.org/fhir/ValueSet/observation-category)

      Codes for high level observation categories.

      TypeCodeableConcept(Codeable Concept (IPS))
      Is Modifierfalse
      Requirements

      Used for filtering what observations are retrieved and displayed.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      SlicingThis element introduces a set of slices on Observation.category. The slices areUnordered and Open, and can be differentiated using the following discriminators:
      • pattern @ $this
      • 28. Observation.category.id
        Definition

        Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

        ShortUnique id for inter-element referencing
        Control0..1
        Typestring
        Is Modifierfalse
        XML FormatIn the XML format, this property is represented as an attribute.
        Summaryfalse
        30. Observation.category.extension
        Definition

        May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

        ShortAdditional content defined by implementations
        Comments

        There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

        Control0..*
        TypeExtension
        Is Modifierfalse
        Summaryfalse
        Alternate Namesextensions, user content
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
        SlicingThis element introduces a set of slices on Observation.category.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
        • value @ url
        • 32. Observation.category.coding
          Definition

          A reference to a code defined by a terminology system.

          ShortA reference to a code defined by a terminology system
          Comments

          Codes may be defined very casually in enumerations or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information.

          Control0..*
          This element is affected by the following invariants: ele-1
          TypeCoding(Coding with translations)
          Is Modifierfalse
          Must Supporttrue
          Requirements

          Allows for alternative encodings within a code system, and translations to other code systems.

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          34. Observation.category.coding.id
          Definition

          Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

          ShortUnique id for inter-element referencing
          Control0..1
          Typestring
          Is Modifierfalse
          XML FormatIn the XML format, this property is represented as an attribute.
          Summaryfalse
          36. Observation.category.coding.extension
          Definition

          May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

          ShortAdditional content defined by implementations
          Comments

          There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

          Control0..*
          TypeExtension
          Is Modifierfalse
          Summaryfalse
          Alternate Namesextensions, user content
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
          SlicingThis element introduces a set of slices on Observation.category.coding.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
          • value @ url
          • 38. Observation.category.coding.system
            Definition

            The identification of the code system that defines the meaning of the symbol in the code.

            ShortIdentity of the terminology system
            Comments

            The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously.

            Control0..1
            Typeuri
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supporttrue
            Summarytrue
            Requirements

            Need to be unambiguous about the source of the definition of the symbol.

            Pattern Valuehttp://terminology.hl7.org/CodeSystem/observation-category
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            40. Observation.category.coding.version
            Definition

            The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged.

            ShortVersion of the system - if relevant
            Comments

            Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date.

            NoteThis is a business version Id, not a resource version Id (see discussion)
            Control0..1
            Typestring
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            42. Observation.category.coding.code
            Definition

            A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).

            ShortSymbol in syntax defined by the system
            Control0..1
            Typecode
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supporttrue
            Summarytrue
            Requirements

            Need to refer to a particular code in the system.

            Pattern Valuelaboratory
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            44. Observation.category.coding.display
            Definition

            A representation of the meaning of the code in the system, following the rules of the system.

            ShortRepresentation defined by the system
            Control0..1
            Typestring
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supporttrue
            Summarytrue
            Requirements

            Need to be able to carry a human-readable meaning of the code for readers that do not know the system.

            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            46. Observation.category.coding.display.id
            Definition

            unique id for the element within a resource (for internal references)

            Shortxml:id (or equivalent in JSON)
            Control0..1
            Typestring
            Is Modifierfalse
            XML FormatIn the XML format, this property is represented as an attribute.
            Summaryfalse
            48. Observation.category.coding.display.extension
            Definition

            An Extension

            ShortExtension
            Control0..*
            TypeExtension
            Is Modifierfalse
            Summaryfalse
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
            SlicingThis element introduces a set of slices on Observation.category.coding.display.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
            • value @ url
            • 50. Observation.category.coding.display.extension:translation
              Slice Nametranslation
              Definition

              Language translation from base language of resource to another language.

              ShortLanguage Translation (Localization)
              Control0..*
              This element is affected by the following invariants: ele-1
              TypeExtension(Translation) (Complex Extension)
              Is Modifierfalse
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
              52. Observation.category.coding.display.value
              Definition

              The actual value

              ShortPrimitive value for string
              Control0..1
              Typestring
              Is Modifierfalse
              XML FormatIn the XML format, this property is represented as an attribute.
              Summaryfalse
              Max Length:1048576
              54. Observation.category.coding.userSelected
              Definition

              Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).

              ShortIf this coding was chosen directly by the user
              Comments

              Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely.

              Control0..1
              Typeboolean
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Summarytrue
              Requirements

              This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.

              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              56. Observation.category.text
              Definition

              A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.

              ShortPlain text representation of the concept
              Comments

              Very often the text is the same as a displayName of one of the codings.

              Control0..1
              Typestring
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Must Supporttrue
              Summarytrue
              Requirements

              The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              58. Observation.category:laboratory
              Slice Namelaboratory
              Definition

              A concept that may be defined by a formal reference to a terminology or ontology or may be provided by text.

              ShortConcept - reference to a terminology or just text
              Comments

              Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination.

              Control1..1
              This element is affected by the following invariants: ele-1
              BindingThe codes SHOULD be taken from ObservationCategoryCodes
              (preferred to http://hl7.org/fhir/ValueSet/observation-category)

              Codes for high level observation categories.

              TypeCodeableConcept(Codeable Concept (IPS))
              Is Modifierfalse
              Must Supporttrue
              Requirements

              Used for filtering what observations are retrieved and displayed.

              Pattern Value{
                "coding" : [{
                  "system" : "http://terminology.hl7.org/CodeSystem/observation-category",
                  "code" : "laboratory"
                }]
              }
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              60. Observation.code
              Definition

              Describes what was observed. Sometimes this is called the observation "name". In this profile this code represents either a simple laboratory test or a laboratory study with multiple child observations

              ShortConcept - reference to a terminology or just text
              Comments

              In the context of this Observation-laboratory-uv-ips profile, when the observation plays the role of a grouper of member sub-observations, the code represent the group (for instance a panel code). In case no code is available, at least a text shall be provided.

              Control1..1
              This element is affected by the following invariants: ele-1
              BindingThe codes SHOULD be taken from Results Laboratory Observation - IPS
              (preferred to http://hl7.org/fhir/uv/ips/ValueSet/results-laboratory-observations-uv-ips)
              TypeCodeableConcept(Codeable Concept (IPS))
              Is Modifierfalse
              Must Supporttrue
              Requirements

              Knowing what kind of observation is being made is essential to understanding the observation.

              Pattern Value{
                "coding" : [{
                  "system" : "http://loinc.org",
                  "code" : "76629-5"
                }]
              }
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              62. Observation.code.id
              Definition

              Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

              ShortUnique id for inter-element referencing
              Control0..1
              Typestring
              Is Modifierfalse
              XML FormatIn the XML format, this property is represented as an attribute.
              Summaryfalse
              64. Observation.code.extension
              Definition

              May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

              ShortAdditional content defined by implementations
              Comments

              There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

              Control0..*
              TypeExtension
              Is Modifierfalse
              Summaryfalse
              Alternate Namesextensions, user content
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
              SlicingThis element introduces a set of slices on Observation.code.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
              • value @ url
              • 66. Observation.code.coding
                Definition

                A reference to a code defined by a terminology system.

                ShortA reference to a code defined by a terminology system
                Comments

                Codes may be defined very casually in enumerations or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information.

                Control0..*
                This element is affected by the following invariants: ele-1
                TypeCoding(Coding with translations)
                Is Modifierfalse
                Must Supporttrue
                Requirements

                Allows for alternative encodings within a code system, and translations to other code systems.

                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                68. Observation.code.text
                Definition

                A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.

                ShortPlain text representation of the concept
                Comments

                Very often the text is the same as a displayName of one of the codings.

                Control0..1
                Typestring
                Is Modifierfalse
                Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                Must Supporttrue
                Summarytrue
                Requirements

                The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

                Pattern ValueFasting glucose
                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                70. Observation.subject
                Definition

                The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the focus element or the code itself specifies the actual focus of the observation.

                ShortWho and/or what the observation is about
                Comments

                One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated.

                Control1..1
                TypeReference(Patient)
                Is Modifierfalse
                Must Supporttrue
                Summarytrue
                Requirements

                Observations have no value if you don't know who or what they're about.

                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                72. Observation.subject.id
                Definition

                Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

                ShortUnique id for inter-element referencing
                Control0..1
                Typestring
                Is Modifierfalse
                XML FormatIn the XML format, this property is represented as an attribute.
                Summaryfalse
                74. Observation.subject.extension
                Definition

                May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

                ShortAdditional content defined by implementations
                Comments

                There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                Control0..*
                TypeExtension
                Is Modifierfalse
                Summaryfalse
                Alternate Namesextensions, user content
                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                SlicingThis element introduces a set of slices on Observation.subject.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                • value @ url
                • 76. Observation.subject.reference
                  Definition

                  A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

                  ShortLiteral reference, Relative, internal or absolute URL
                  Comments

                  Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

                  Control1..1
                  This element is affected by the following invariants: ref-1
                  Typestring
                  Is Modifierfalse
                  Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                  Must Supporttrue
                  Summarytrue
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  78. Observation.subject.type
                  Definition

                  The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

                  The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

                  ShortType the reference refers to (e.g. "Patient")
                  Comments

                  This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified.

                  Control0..1
                  BindingUnless not suitable, these codes SHALL be taken from ResourceType
                  (extensible to http://hl7.org/fhir/ValueSet/resource-types)

                  Aa resource (or, for logical models, the URI of the logical model).

                  Typeuri
                  Is Modifierfalse
                  Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                  Summarytrue
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  80. Observation.subject.identifier
                  Definition

                  An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

                  ShortLogical reference, when literal reference is not known
                  Comments

                  When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

                  When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

                  Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

                  Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

                  NoteThis is a business identifier, not a resource identifier (see discussion)
                  Control0..1
                  TypeIdentifier
                  Is Modifierfalse
                  Summarytrue
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  82. Observation.subject.display
                  Definition

                  Plain text narrative that identifies the resource in addition to the resource reference.

                  ShortText alternative for the resource
                  Comments

                  This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

                  Control0..1
                  Typestring
                  Is Modifierfalse
                  Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                  Summarytrue
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  84. Observation.focus
                  Definition

                  The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus.

                  ShortWhat the observation is about, when it is not about the subject of record
                  Comments

                  Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use specimen if a reference to a specimen is required. If a code is required instead of a resource use either bodysite for bodysites or the standard extension focusCode.

                  Control0..*
                  TypeReference(Resource)
                  Is Modifierfalse
                  Summarytrue
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  86. Observation.encounter
                  Definition

                  The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made.

                  ShortHealthcare event during which this observation is made
                  Comments

                  This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests).

                  Control0..1
                  TypeReference(Target Facility Encounter)
                  Is Modifierfalse
                  Summarytrue
                  Requirements

                  For some observations it may be important to know the link between an observation and a particular encounter.

                  Alternate NamesContext
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  88. Observation.effective[x]
                  Definition

                  The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself.

                  ShortClinically relevant time/time-period for observation
                  Comments

                  At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the Timing datatype which allow the measurement to be tied to regular life events.

                  Control1..1
                  TypeChoice of: dateTime, Period
                  [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                  Is Modifierfalse
                  Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                  Must Supporttrue
                  Must Support TypesNo must-support rules about the choice of types/profiles
                  Summarytrue
                  Requirements

                  Knowing when an observation was deemed true is important to its relevance as well as determining trends.

                  Alternate NamesOccurrence
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  90. Observation.effective[x].id
                  Definition

                  Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

                  ShortUnique id for inter-element referencing
                  Control0..1
                  Typestring
                  Is Modifierfalse
                  XML FormatIn the XML format, this property is represented as an attribute.
                  Summaryfalse
                  92. Observation.effective[x].extension
                  Definition

                  May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

                  ShortAdditional content defined by implementations
                  Comments

                  There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                  Control0..*
                  TypeExtension
                  Is Modifierfalse
                  Summaryfalse
                  Alternate Namesextensions, user content
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                  SlicingThis element introduces a set of slices on Observation.effective[x].extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                  • value @ url
                  • 94. Observation.effective[x].extension:data-absent-reason
                    Slice Namedata-absent-reason
                    Definition

                    Provides a reason why the effectiveTime is missing.

                    Shorteffective[x] absence reason
                    Control0..1
                    TypeExtension(Data Absent Reason) (Extension Type: code)
                    Is Modifierfalse
                    Must Supporttrue
                    Summaryfalse
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                    96. Observation.issued
                    Definition

                    The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified.

                    ShortDate/Time this version was made available
                    Comments

                    For Observations that don’t require review and verification, it may be the same as the lastUpdated time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the lastUpdated time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again.

                    Control0..1
                    Typeinstant
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    98. Observation.performer
                    Definition

                    Who was responsible for asserting the observed value as "true".

                    ShortWho is responsible for the observation
                    Control1..*
                    TypeReference(Practitioner, Organization)
                    Is Modifierfalse
                    Must Supporttrue
                    Must Support TypesNo must-support rules about the choice of types/profiles
                    Summarytrue
                    Requirements

                    May give a degree of confidence in the observation and also indicates where follow-up questions should be directed.

                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    100. Observation.value[x]
                    Definition

                    The information determined as a result of making the observation, if the information has a simple value.

                    ShortActual result
                    Comments

                    An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

                    Control0..1
                    This element is affected by the following invariants: obs-7
                    TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
                    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Must Supporttrue
                    Must Support TypesNo must-support rules about the choice of types/profiles
                    Summarytrue
                    Requirements

                    An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    SlicingThis element introduces a set of slices on Observation.value[x]. The slices areUnordered and Closed, and can be differentiated using the following discriminators:
                    • type @ $this
                    • 102. Observation.value[x]:valueQuantity
                      Slice NamevalueQuantity
                      Definition

                      A measured amount (or an amount that can potentially be measured). Note that measured amounts include amounts that are not precisely quantified, including amounts involving arbitrary units and floating currencies. This profile imposes that the code system for units be UCUM.

                      ShortA measured amount using UCUM
                      Comments

                      The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator.

                      Control0..1
                      This element is affected by the following invariants: ele-1
                      TypeQuantity(Quantity (IPS))
                      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                      Is Modifierfalse
                      Must Supporttrue
                      Requirements

                      An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      qty-3: If a code for the unit is present, the system SHALL also be present (code.empty() or system.exists())
                      104. Observation.value[x]:valueQuantity.id
                      Definition

                      Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

                      ShortUnique id for inter-element referencing
                      Control0..1
                      Typestring
                      Is Modifierfalse
                      XML FormatIn the XML format, this property is represented as an attribute.
                      Summaryfalse
                      106. Observation.value[x]:valueQuantity.extension
                      Definition

                      May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

                      ShortAdditional content defined by implementations
                      Comments

                      There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                      Control0..*
                      TypeExtension
                      Is Modifierfalse
                      Summaryfalse
                      Alternate Namesextensions, user content
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                      SlicingThis element introduces a set of slices on Observation.value[x].extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                      • value @ url
                      • 108. Observation.value[x]:valueQuantity.value
                        Definition

                        The value of the measured amount. The value includes an implicit precision in the presentation of the value.

                        ShortNumerical value (with implicit precision)
                        Comments

                        The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books).

                        Control1..1
                        Typedecimal
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Summarytrue
                        Requirements

                        Precision is handled implicitly in almost all cases of measurement.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        110. Observation.value[x]:valueQuantity.comparator
                        Definition

                        How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value.

                        Short< | <= | >= | > - how to understand the value
                        Control0..1
                        BindingThe codes SHALL be taken from QuantityComparator
                        (required to http://hl7.org/fhir/ValueSet/quantity-comparator|4.0.1)

                        How the Quantity should be understood and represented.

                        Typecode
                        Is Modifiertrue because This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Summarytrue
                        Requirements

                        Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.

                        Meaning if MissingIf there is no comparator, then there is no modification of the value
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        112. Observation.value[x]:valueQuantity.unit
                        Definition

                        A human-readable form of the unit.

                        ShortUnit representation
                        Control0..1
                        Typestring
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Summarytrue
                        Requirements

                        There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.

                        Pattern Valuemmol/L
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        114. Observation.value[x]:valueQuantity.system
                        Definition

                        The identification of the system that provides the coded form of the unit.

                        ShortUCUM system for units
                        Control1..1
                        This element is affected by the following invariants: qty-3
                        Typeuri
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Must Supporttrue
                        Summarytrue
                        Requirements

                        Need to know the system that defines the coded form of the unit.

                        Fixed Valuehttp://unitsofmeasure.org
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        116. Observation.value[x]:valueQuantity.code
                        Definition

                        A computer processable form of the unit in some unit representation system.

                        ShortCoded form of the unit
                        Comments

                        The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system.

                        Control1..1
                        Typecode
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Must Supporttrue
                        Summarytrue
                        Requirements

                        Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest.

                        Pattern Valuemmol/L
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        118. Observation.value[x]:valueString
                        Slice NamevalueString
                        Definition

                        The information determined as a result of making the observation, if the information has a simple value.

                        ShortActual result
                        Comments

                        An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

                        Control0..1
                        This element is affected by the following invariants: obs-7
                        Typestring
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Must Supporttrue
                        Summarytrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        120. Observation.value[x]:valueRange
                        Slice NamevalueRange
                        Definition

                        A set of ordered Quantities defined by a low and high limit.

                        ShortSet of values bounded by low and high
                        Comments

                        The stated low and high value are assumed to have arbitrarily high precision when it comes to determining which values are in the range. I.e. 1.99 is not in the range 2 -> 3.

                        Control0..1
                        This element is affected by the following invariants: ele-1
                        TypeRange(Range (IPS))
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Must Supporttrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        rng-2: If present, low SHALL have a lower value than high (low.empty() or high.empty() or (low <= high))
                        122. Observation.value[x]:valueRatio
                        Slice NamevalueRatio
                        Definition

                        A relationship of two Quantity values - expressed as a numerator and a denominator.

                        ShortA ratio of two Quantity values - a numerator and a denominator
                        Comments

                        The Ratio datatype should only be used to express a relationship of two numbers if the relationship cannot be suitably expressed using a Quantity and a common unit. Where the denominator value is known to be fixed to "1", Quantity should be used instead of Ratio.

                        Control0..1
                        This element is affected by the following invariants: ele-1
                        TypeRatio(Ratio (IPS))
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Must Supporttrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        rat-1: Numerator and denominator SHALL both be present, or both are absent. If both are absent, there SHALL be some extension present ((numerator.empty() xor denominator.exists()) and (numerator.exists() or extension.exists()))
                        124. Observation.value[x]:valueTime
                        Slice NamevalueTime
                        Definition

                        The information determined as a result of making the observation, if the information has a simple value.

                        ShortActual result
                        Comments

                        An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

                        Control0..1
                        This element is affected by the following invariants: obs-7
                        Typetime
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Must Supporttrue
                        Summarytrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        126. Observation.value[x]:valueDateTime
                        Slice NamevalueDateTime
                        Definition

                        The information determined as a result of making the observation, if the information has a simple value.

                        ShortActual result
                        Comments

                        An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

                        Control0..1
                        This element is affected by the following invariants: obs-7
                        TypedateTime
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Must Supporttrue
                        Summarytrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        128. Observation.value[x]:valuePeriod
                        Slice NamevaluePeriod
                        Definition

                        The information determined as a result of making the observation, if the information has a simple value.

                        ShortActual result
                        Comments

                        An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

                        Control0..1
                        This element is affected by the following invariants: obs-7
                        TypePeriod
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Must Supporttrue
                        Summarytrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        130. Observation.value[x]:valueCodeableConcept
                        Slice NamevalueCodeableConcept
                        Definition

                        A concept that may be defined by a formal reference to a terminology or ontology or may be provided by text.

                        ShortConcept - reference to a terminology or just text
                        Comments

                        Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination.

                        Control0..1
                        This element is affected by the following invariants: ele-1
                        BindingThe codes SHOULD be taken from Results Coded Values Laboratory - IPS
                        (preferred to http://hl7.org/fhir/uv/ips/ValueSet/results-coded-values-laboratory-uv-ips)
                        TypeCodeableConcept(Codeable Concept (IPS))
                        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                        Is Modifierfalse
                        Must Supporttrue
                        Requirements

                        An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        132. Observation.dataAbsentReason
                        Definition

                        Provides a reason why the expected value in the element Observation.value[x] is missing.

                        ShortWhy the result is missing
                        Comments

                        Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory".

                        The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values.

                        Control0..1
                        This element is affected by the following invariants: obs-6
                        BindingUnless not suitable, these codes SHALL be taken from DataAbsentReason
                        (extensible to http://hl7.org/fhir/ValueSet/data-absent-reason)

                        Codes specifying why the result (Observation.value[x]) is missing.

                        TypeCodeableConcept
                        Is Modifierfalse
                        Summaryfalse
                        Requirements

                        For many results it is necessary to handle exceptional values in measurements.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        134. Observation.interpretation
                        Definition

                        reason(s) why this should be supported.

                        ShortConcept - reference to a terminology or just text
                        Comments

                        Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination.

                        Control0..*
                        This element is affected by the following invariants: ele-1
                        BindingUnless not suitable, these codes SHALL be taken from ObservationInterpretationCodes
                        (extensible to http://hl7.org/fhir/ValueSet/observation-interpretation)

                        Codes identifying interpretations of observations.

                        TypeCodeableConcept(Codeable Concept (IPS))
                        Is Modifierfalse
                        Must Supporttrue
                        Requirements

                        For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        136. Observation.note
                        Definition

                        Comments about the observation or the results.

                        ShortComments about the observation
                        Comments

                        May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation.

                        Control0..*
                        TypeAnnotation
                        Is Modifierfalse
                        Summaryfalse
                        Requirements

                        Need to be able to provide free text additional information.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        138. Observation.bodySite
                        Definition

                        Indicates the site on the subject's body where the observation was made (i.e. the target site).

                        ShortObserved body part
                        Comments

                        Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component.

                        If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension bodySite.

                        Control0..1
                        BindingFor example codes, see SNOMEDCTBodyStructures
                        (example to http://hl7.org/fhir/ValueSet/body-site)

                        Codes describing anatomical locations. May include laterality.

                        TypeCodeableConcept
                        Is Modifierfalse
                        Summaryfalse
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        140. Observation.method
                        Definition

                        Indicates the mechanism used to perform the observation.

                        ShortHow it was done
                        Comments

                        Only used if not implicit in code for Observation.code.

                        Control0..1
                        BindingFor example codes, see ObservationMethods
                        (example to http://hl7.org/fhir/ValueSet/observation-methods)

                        Methods for simple observations.

                        TypeCodeableConcept
                        Is Modifierfalse
                        Summaryfalse
                        Requirements

                        In some cases, method can impact results and is thus used for determining whether results can be compared or determining significance of results.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        142. Observation.specimen
                        Definition

                        The specimen that was used when this observation was made.

                        ShortSpecimen used for this observation
                        Comments

                        Should only be used if not implicit in code found in Observation.code. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report).

                        Control0..1
                        TypeReference(Specimen (IPS))
                        Is Modifierfalse
                        Summaryfalse
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        144. Observation.device
                        Definition

                        The device used to generate the observation data.

                        Short(Measurement) Device
                        Comments

                        Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant.

                        Control1..1
                        TypeReference(Device Information)
                        Is Modifierfalse
                        Summaryfalse
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        146. Observation.referenceRange
                        Definition

                        reason(s) why this should be supported.

                        ShortProvides guide for interpretation
                        Comments

                        Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties.

                        Control0..*
                        TypeBackboneElement
                        Is Modifierfalse
                        Must Supporttrue
                        Summaryfalse
                        Requirements

                        Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        obs-3: Must have at least a low or a high or text (low.exists() or high.exists() or text.exists())
                        148. Observation.referenceRange.id
                        Definition

                        Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

                        ShortUnique id for inter-element referencing
                        Control0..1
                        Typestring
                        Is Modifierfalse
                        XML FormatIn the XML format, this property is represented as an attribute.
                        Summaryfalse
                        150. Observation.referenceRange.extension
                        Definition

                        May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

                        ShortAdditional content defined by implementations
                        Comments

                        There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                        Control0..*
                        TypeExtension
                        Is Modifierfalse
                        Summaryfalse
                        Alternate Namesextensions, user content
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                        152. Observation.referenceRange.modifierExtension
                        Definition

                        May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

                        Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

                        ShortExtensions that cannot be ignored even if unrecognized
                        Comments

                        There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                        Control0..*
                        TypeExtension
                        Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
                        Summarytrue
                        Requirements

                        Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

                        Alternate Namesextensions, user content, modifiers
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                        154. Observation.referenceRange.low
                        Definition

                        The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3).

                        ShortLow Range, if relevant
                        Control0..1
                        This element is affected by the following invariants: obs-3
                        TypeQuantity(SimpleQuantity)
                        Is Modifierfalse
                        Summaryfalse
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        156. Observation.referenceRange.high
                        Definition

                        The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3).

                        ShortHigh Range, if relevant
                        Control0..1
                        This element is affected by the following invariants: obs-3
                        TypeQuantity(SimpleQuantity)
                        Is Modifierfalse
                        Summaryfalse
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        158. Observation.referenceRange.type
                        Definition

                        Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range.

                        ShortReference range qualifier
                        Comments

                        This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed.

                        Control0..1
                        BindingThe codes SHOULD be taken from ObservationReferenceRangeMeaningCodes
                        (preferred to http://hl7.org/fhir/ValueSet/referencerange-meaning)

                        Code for the meaning of a reference range.

                        TypeCodeableConcept
                        Is Modifierfalse
                        Summaryfalse
                        Requirements

                        Need to be able to say what kind of reference range this is - normal, recommended, therapeutic, etc., - for proper interpretation.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        160. Observation.referenceRange.appliesTo
                        Definition

                        Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple appliesTo are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used.

                        ShortReference range population
                        Comments

                        This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed.

                        Control0..*
                        BindingFor example codes, see ObservationReferenceRangeAppliesToCodes
                        (example to http://hl7.org/fhir/ValueSet/referencerange-appliesto)

                        Codes identifying the population the reference range applies to.

                        TypeCodeableConcept
                        Is Modifierfalse
                        Summaryfalse
                        Requirements

                        Need to be able to identify the target population for proper interpretation.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        162. Observation.referenceRange.age
                        Definition

                        The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so.

                        ShortApplicable age range, if relevant
                        Control0..1
                        TypeRange
                        Is Modifierfalse
                        Summaryfalse
                        Requirements

                        Some analytes vary greatly over age.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        164. Observation.referenceRange.text
                        Definition

                        Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals".

                        ShortText based reference range in an observation
                        Control0..1
                        Typestring
                        Is Modifierfalse
                        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                        Summaryfalse
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        166. Observation.hasMember
                        Definition

                        A reference to another Observation profiled by Observation-results-laboratory-uv-ips. The target observation (for instance an individual test member of a panel) is considered as a sub-observation of the current one, which plays the role of a grouper.

                        ShortRelated resource that belongs to the Observation group
                        Comments

                        This element is used in the context of international patient summary when there is a need to group a collection of observations, because they belong to the same panel, or because they share a common interpretation comment, or a common media attachment (illustrative image or graph). In these cases, the current observation is the grouper, and its set of sub-observations are related observations using the type "has-member". For a discussion on the ways Observations can be assembled in groups together see Observation Grouping.

                        Control0..*
                        TypeReference(Observation Results: laboratory (IPS), Observation Results (IPS))
                        Is Modifierfalse
                        Summarytrue
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        168. Observation.hasMember.id
                        Definition

                        Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

                        ShortUnique id for inter-element referencing
                        Control0..1
                        Typestring
                        Is Modifierfalse
                        XML FormatIn the XML format, this property is represented as an attribute.
                        Summaryfalse
                        170. Observation.hasMember.extension
                        Definition

                        May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

                        ShortAdditional content defined by implementations
                        Comments

                        There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                        Control0..*
                        TypeExtension
                        Is Modifierfalse
                        Summaryfalse
                        Alternate Namesextensions, user content
                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                        SlicingThis element introduces a set of slices on Observation.hasMember.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                        • value @ url
                        • 172. Observation.hasMember.reference
                          Definition

                          A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

                          ShortLiteral reference, Relative, internal or absolute URL
                          Comments

                          Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

                          Control0..1
                          This element is affected by the following invariants: ref-1
                          Typestring
                          Is Modifierfalse
                          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                          Summarytrue
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          174. Observation.hasMember.type
                          Definition

                          The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

                          The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

                          ShortType the reference refers to (e.g. "Patient")
                          Comments

                          This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified.

                          Control0..1
                          BindingUnless not suitable, these codes SHALL be taken from ResourceType
                          (extensible to http://hl7.org/fhir/ValueSet/resource-types)

                          Aa resource (or, for logical models, the URI of the logical model).

                          Typeuri
                          Is Modifierfalse
                          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                          Summarytrue
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          176. Observation.hasMember.identifier
                          Definition

                          An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

                          ShortLogical reference, when literal reference is not known
                          Comments

                          When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

                          When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

                          Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

                          Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

                          NoteThis is a business identifier, not a resource identifier (see discussion)
                          Control0..1
                          TypeIdentifier
                          Is Modifierfalse
                          Summarytrue
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          178. Observation.hasMember.display
                          Definition

                          Plain text narrative that identifies the resource in addition to the resource reference.

                          ShortText alternative for the resource
                          Comments

                          This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

                          Control0..1
                          Typestring
                          Is Modifierfalse
                          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                          Summarytrue
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          180. Observation.derivedFrom
                          Definition

                          The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image.

                          ShortRelated measurements the observation is made from
                          Comments

                          All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see Notes below.

                          Control0..*
                          TypeReference(DocumentReference, ImagingStudy, Media, QuestionnaireResponse, Observation, MolecularSequence)
                          Is Modifierfalse
                          Summarytrue
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          182. Observation.component
                          Definition

                          Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations.

                          ShortComponent results
                          Comments

                          For a discussion on the ways Observations can be assembled in groups together see Notes below.

                          Control0..*
                          TypeBackboneElement
                          Is Modifierfalse
                          Must Supporttrue
                          Summarytrue
                          Requirements

                          Component observations share the same attributes in the Observation resource as the primary observation and are always treated a part of a single observation (they are not separable). However, the reference range for the primary observation value is not inherited by the component values and is required when appropriate for each component observation.

                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          184. Observation.component.id
                          Definition

                          Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

                          ShortUnique id for inter-element referencing
                          Control0..1
                          Typestring
                          Is Modifierfalse
                          XML FormatIn the XML format, this property is represented as an attribute.
                          Summaryfalse
                          186. Observation.component.extension
                          Definition

                          May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

                          ShortAdditional content defined by implementations
                          Comments

                          There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                          Control0..*
                          TypeExtension
                          Is Modifierfalse
                          Summaryfalse
                          Alternate Namesextensions, user content
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                          188. Observation.component.modifierExtension
                          Definition

                          May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

                          Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

                          ShortExtensions that cannot be ignored even if unrecognized
                          Comments

                          There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

                          Control0..*
                          TypeExtension
                          Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
                          Summarytrue
                          Requirements

                          Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

                          Alternate Namesextensions, user content, modifiers
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                          190. Observation.component.code
                          Definition

                          Describes what was observed. Sometimes this is called the observation "code".

                          ShortType of component observation (code / type)
                          Comments

                          All code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation.

                          Control1..1
                          BindingFor example codes, see LOINCCodes
                          (example to http://hl7.org/fhir/ValueSet/observation-codes)

                          Codes identifying names of simple observations.

                          TypeCodeableConcept
                          Is Modifierfalse
                          Summarytrue
                          Requirements

                          Knowing what kind of observation is being made is essential to understanding the observation.

                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          192. Observation.component.value[x]
                          Definition

                          The information determined as a result of making the observation, if the information has a simple value.

                          ShortActual component result
                          Comments

                          Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

                          Control0..1
                          TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
                          [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                          Is Modifierfalse
                          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                          Summarytrue
                          Requirements

                          An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          194. Observation.component.dataAbsentReason
                          Definition

                          Provides a reason why the expected value in the element Observation.component.value[x] is missing.

                          ShortWhy the component result is missing
                          Comments

                          "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done".

                          The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values.

                          Control0..1
                          This element is affected by the following invariants: obs-6
                          BindingUnless not suitable, these codes SHALL be taken from DataAbsentReason
                          (extensible to http://hl7.org/fhir/ValueSet/data-absent-reason)

                          Codes specifying why the result (Observation.value[x]) is missing.

                          TypeCodeableConcept
                          Is Modifierfalse
                          Summaryfalse
                          Requirements

                          For many results it is necessary to handle exceptional values in measurements.

                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          196. Observation.component.interpretation
                          Definition

                          A categorical assessment of an observation value. For example, high, low, normal.

                          ShortHigh, low, normal, etc.
                          Comments

                          Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result.

                          Control0..*
                          BindingUnless not suitable, these codes SHALL be taken from ObservationInterpretationCodes
                          (extensible to http://hl7.org/fhir/ValueSet/observation-interpretation)

                          Codes identifying interpretations of observations.

                          TypeCodeableConcept
                          Is Modifierfalse
                          Summaryfalse
                          Requirements

                          For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result.

                          Alternate NamesAbnormal Flag
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          198. Observation.component.referenceRange
                          Definition

                          Guidance on how to interpret the value by comparison to a normal or recommended range.

                          ShortProvides guide for interpretation of component result
                          Comments

                          Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties.

                          Control0..*
                          TypeSeettp://hl7.org/fhir/StructureDefinition/Observation#Observation.referenceRange
                          Is Modifierfalse
                          Summaryfalse
                          Requirements

                          Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts.

                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))