0.1.0 - ci-build

HIVFHIRIG, published by intellisoftkenya. 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/IntelliSOFT-Consulting/HIV-FHIR-IG/ and changes regularly. See the Directory of published versions

Resource Profile: ObservationProfile - Detailed Descriptions

Draft as of 2024-09-18

Definitions for the ObservationProfile resource profile.

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

0. Observation
2. Observation.identifier
NoteThis is a business identifier, not a resource identifier (see discussion)
Must Supporttrue
4. Observation.identifier.system
Control1..?
Must Supporttrue
6. Observation.identifier.value
Control1..?
Must Supporttrue
8. Observation.status
Must Supporttrue
10. Observation.category
Must Supporttrue
12. Observation.code
Must Supporttrue
14. Observation.subject
TypeReference(Patient)
Must Supporttrue
16. Observation.effective[x]
[x] NoteSeeChoice of Data Typesfor further information about how to use [x]
Must Supporttrue
SlicingThis element introduces a set of slices on Observation.effective[x]. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • type @ $this
  • 18. Observation.effective[x]:effectiveDateTime
    Slice NameeffectiveDateTime
    Control0..1
    TypedateTime
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    20. Observation.effective[x]:effectivePeriod
    Slice NameeffectivePeriod
    Control0..1
    TypePeriod
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Must Supporttrue
    22. Observation.issued
    Must Supporttrue
    24. Observation.value[x]
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Must Supporttrue
    SlicingThis element introduces a set of slices on Observation.value[x]. The slices areUnordered and Open, and can be differentiated using the following discriminators:
    • type @ $this
    • 26. Observation.value[x]:valueQuantity
      Slice NamevalueQuantity
      Control0..1
      TypeQuantity
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Must Supporttrue
      28. Observation.value[x]:valueCodeableConcept
      Slice NamevalueCodeableConcept
      Control0..1
      TypeCodeableConcept
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Must Supporttrue
      30. Observation.value[x]:valueString
      Slice NamevalueString
      Control0..1
      Typestring
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      32. Observation.value[x]:valueBoolean
      Slice NamevalueBoolean
      Control0..1
      Typeboolean
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      34. Observation.value[x]:valueInteger
      Slice NamevalueInteger
      Control0..1
      Typeinteger
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      36. Observation.value[x]:valueRange
      Slice NamevalueRange
      Control0..1
      TypeRange
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Must Supporttrue
      38. Observation.value[x]:valueTime
      Slice NamevalueTime
      Control0..1
      Typetime
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      40. Observation.value[x]:valueDateTime
      Slice NamevalueDateTime
      Control0..1
      TypedateTime
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      42. Observation.dataAbsentReason
      Must Supporttrue
      44. Observation.interpretation
      Must Supporttrue
      46. Observation.bodySite
      Must Supporttrue
      48. Observation.method
      Must Supporttrue
      50. Observation.referenceRange
      Must Supporttrue
      52. Observation.component
      54. Observation.component.code
      Must Supporttrue
      56. Observation.component.value[x]
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      Must Supporttrue

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

      0. Observation
      Definition

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

      ShortMeasurements and simple assertions
      Comments

      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())
      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.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
      Must Supporttrue
      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()))
      8. Observation.identifier.use
      Definition

      The purpose of this identifier.

      Shortusual | official | temp | secondary | old (If known)
      Comments

      Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

      Control0..1
      BindingThe codes SHALL be taken from IdentifierUsehttp://hl7.org/fhir/ValueSet/identifier-use|4.0.1
      (required to http://hl7.org/fhir/ValueSet/identifier-use|4.0.1)

      Identifies the purpose for this identifier, if known .

      Typecode
      Is Modifiertrue because This is labeled as "Is Modifier" because applications should not mistake a temporary id for a permanent one.
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

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

      Establishes the namespace for the value - that is, a URL that describes a set values that are unique.

      ShortThe namespace for the identifier value
      Comments

      Identifier.system is always case sensitive.

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

      There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

      Example<br/><b>General</b>:http://www.acme.com/identifiers/patient
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      12. Observation.identifier.value
      Definition

      The portion of the identifier typically relevant to the user and which is unique within the context of the system.

      ShortThe value that is unique
      Comments

      If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

      Control10..1
      Typestring
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Example<br/><b>General</b>:123456
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      14. 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
      Must Supporttrue
      Summarytrue
      Requirements

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

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

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

      ShortClassification of type of observation
      Comments

      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.

      Control0..*
      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
      Is Modifierfalse
      Must Supporttrue
      Summaryfalse
      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()))
      18. Observation.code
      Definition

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

      ShortType of observation (code / type)
      Comments

      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
      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
      Must Supporttrue
      Summarytrue
      Requirements

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

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

      Control0..1
      TypeReference(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()))
      22. 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.

      Control0..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()))
      SlicingThis element introduces a set of slices on Observation.effective[x]. The slices areUnordered and Open, and can be differentiated using the following discriminators:
      • type @ $this
      • 24. Observation.effective[x]:effectiveDateTime
        Slice NameeffectiveDateTime
        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.

        Control0..1
        TypedateTime, 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
        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()))
        26. Observation.effective[x]:effectivePeriod
        Slice NameeffectivePeriod
        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.

        Control0..1
        TypePeriod, dateTime, Timing, instant
        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
        Is Modifierfalse
        Must Supporttrue
        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()))
        28. 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
        Must Supporttrue
        Summarytrue
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        30. 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 Open, and can be differentiated using the following discriminators:
        • type @ $this
        • 32. Observation.value[x]:valueQuantity
          Slice NamevalueQuantity
          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
          TypeQuantity, 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
          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()))
          34. Observation.value[x]:valueCodeableConcept
          Slice NamevalueCodeableConcept
          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
          TypeCodeableConcept, 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
          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()))
          36. 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()))
          38. Observation.value[x]:valueBoolean
          Slice NamevalueBoolean
          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
          Typeboolean, dateTime, 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()))
          40. Observation.value[x]:valueInteger
          Slice NamevalueInteger
          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
          Typeinteger, dateTime, boolean, string, SampledData, Quantity, Period, Ratio, 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()))
          42. Observation.value[x]:valueRange
          Slice NamevalueRange
          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
          TypeRange, 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
          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()))
          44. 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()))
          46. 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()))
          48. 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 DataAbsentReasonhttp://hl7.org/fhir/ValueSet/data-absent-reason
          (extensible to http://hl7.org/fhir/ValueSet/data-absent-reason)

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

          TypeCodeableConcept
          Is Modifierfalse
          Must Supporttrue
          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()))
          50. Observation.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 ObservationInterpretationCodeshttp://hl7.org/fhir/ValueSet/observation-interpretation
          (extensible to http://hl7.org/fhir/ValueSet/observation-interpretation)

          Codes identifying interpretations of observations.

          TypeCodeableConcept
          Is Modifierfalse
          Must Supporttrue
          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()))
          52. 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 SNOMEDCTBodyStructureshttp://hl7.org/fhir/ValueSet/body-site
          (example to http://hl7.org/fhir/ValueSet/body-site)

          Codes describing anatomical locations. May include laterality.

          TypeCodeableConcept
          Is Modifierfalse
          Must Supporttrue
          Summaryfalse
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          54. 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 ObservationMethodshttp://hl7.org/fhir/ValueSet/observation-methods
          (example to http://hl7.org/fhir/ValueSet/observation-methods)

          Methods for simple observations.

          TypeCodeableConcept
          Is Modifierfalse
          Must Supporttrue
          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()))
          56. Observation.referenceRange
          Definition

          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())
          58. 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())
          60. 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
          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()))
          62. 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())
          64. 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
          Must Supporttrue
          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()))
          66. 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
          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()))

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

          0. Observation
          Definition

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

          ShortMeasurements and simple assertions
          Comments

          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())
          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
          Must Supporttrue
          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.identifier.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
          22. Observation.identifier.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.identifier.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
          • value @ url
          • 24. Observation.identifier.use
            Definition

            The purpose of this identifier.

            Shortusual | official | temp | secondary | old (If known)
            Comments

            Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

            Control0..1
            BindingThe codes SHALL be taken from IdentifierUse
            (required to http://hl7.org/fhir/ValueSet/identifier-use|4.0.1)

            Identifies the purpose for this identifier, if known .

            Typecode
            Is Modifiertrue because This is labeled as "Is Modifier" because applications should not mistake a temporary id for a permanent one.
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Summarytrue
            Requirements

            Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

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

            A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.

            ShortDescription of identifier
            Comments

            This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.

            Control0..1
            BindingUnless not suitable, these codes SHALL be taken from Identifier Type Codes
            (extensible to http://hl7.org/fhir/ValueSet/identifier-type)

            A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.

            TypeCodeableConcept
            Is Modifierfalse
            Summarytrue
            Requirements

            Allows users to make use of identifiers when the identifier system is not known.

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

            Establishes the namespace for the value - that is, a URL that describes a set values that are unique.

            ShortThe namespace for the identifier value
            Comments

            Identifier.system is always case sensitive.

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

            There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

            Example<br/><b>General</b>:http://www.acme.com/identifiers/patient
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            30. Observation.identifier.value
            Definition

            The portion of the identifier typically relevant to the user and which is unique within the context of the system.

            ShortThe value that is unique
            Comments

            If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

            Control1..1
            Typestring
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supporttrue
            Summarytrue
            Example<br/><b>General</b>:123456
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            32. Observation.identifier.period
            Definition

            Time period during which identifier is/was valid for use.

            ShortTime period when id is/was valid for use
            Control0..1
            TypePeriod
            Is Modifierfalse
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            34. Observation.identifier.assigner
            Definition

            Organization that issued/manages the identifier.

            ShortOrganization that issued id (may be just text)
            Comments

            The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.

            Control0..1
            TypeReference(Organization)
            Is Modifierfalse
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            36. 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()))
            38. 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()))
            40. 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
            Must Supporttrue
            Summarytrue
            Requirements

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

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

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

            ShortClassification of type of observation
            Comments

            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.

            Control0..*
            BindingThe codes SHOULD be taken from ObservationCategoryCodes
            (preferred to http://hl7.org/fhir/ValueSet/observation-category)

            Codes for high level observation categories.

            TypeCodeableConcept
            Is Modifierfalse
            Must Supporttrue
            Summaryfalse
            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()))
            44. Observation.code
            Definition

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

            ShortType of observation (code / type)
            Comments

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

            Codes identifying names of simple observations.

            TypeCodeableConcept
            Is Modifierfalse
            Must Supporttrue
            Summarytrue
            Requirements

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

            Alternate NamesName
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            46. 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.

            Control0..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()))
            48. 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()))
            50. 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(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()))
            52. 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.

            Control0..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()))
            SlicingThis element introduces a set of slices on Observation.effective[x]. The slices areUnordered and Open, and can be differentiated using the following discriminators:
            • type @ $this
            • 54. Observation.effective[x]:effectiveDateTime
              Slice NameeffectiveDateTime
              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.

              Control0..1
              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

              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()))
              56. Observation.effective[x]:effectivePeriod
              Slice NameeffectivePeriod
              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.

              Control0..1
              TypePeriod
              [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
              Is Modifierfalse
              Must Supporttrue
              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()))
              58. 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
              Must Supporttrue
              Summarytrue
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              60. Observation.performer
              Definition

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

              ShortWho is responsible for the observation
              Control0..*
              TypeReference(Practitioner, PractitionerRole, Organization, CareTeam, Patient, RelatedPerson)
              Is Modifierfalse
              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()))
              62. 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 Open, and can be differentiated using the following discriminators:
              • type @ $this
              • 64. Observation.value[x]:valueQuantity
                Slice NamevalueQuantity
                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
                TypeQuantity
                [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()))
                66. Observation.value[x]:valueCodeableConcept
                Slice NamevalueCodeableConcept
                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
                TypeCodeableConcept
                [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]: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()))
                70. Observation.value[x]:valueBoolean
                Slice NamevalueBoolean
                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
                Typeboolean
                [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()))
                72. Observation.value[x]:valueInteger
                Slice NamevalueInteger
                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
                Typeinteger
                [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()))
                74. Observation.value[x]:valueRange
                Slice NamevalueRange
                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
                TypeRange
                [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()))
                76. 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()))
                78. 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()))
                80. 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
                Must Supporttrue
                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()))
                82. Observation.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
                Must Supporttrue
                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()))
                84. 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()))
                86. 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
                Must Supporttrue
                Summaryfalse
                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                88. 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
                Must Supporttrue
                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()))
                90. 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)
                Is Modifierfalse
                Summaryfalse
                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                92. 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.

                Control0..1
                TypeReference(Device, DeviceMetric)
                Is Modifierfalse
                Summaryfalse
                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                94. Observation.referenceRange
                Definition

                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())
                96. 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
                98. 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())
                100. 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())
                102. 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()))
                104. 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()))
                106. 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()))
                108. 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()))
                110. 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()))
                112. 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()))
                114. Observation.hasMember
                Definition

                This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group.

                ShortRelated resource that belongs to the Observation group
                Comments

                When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see Notes below. Note that a system may calculate results from QuestionnaireResponse into a final score and represent the score as an Observation.

                Control0..*
                TypeReference(Observation, QuestionnaireResponse, MolecularSequence)
                Is Modifierfalse
                Summarytrue
                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                116. 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()))
                118. 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
                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()))
                120. 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
                122. 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())
                124. 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())
                126. 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
                Must Supporttrue
                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()))
                128. 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
                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()))
                130. 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()))
                132. 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()))
                134. 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()))