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Orders and Observations icon Work Group  Maturity Level: 0 Trial Use Use Context: Not yet ready for Production use

Definitions for the ldlcholesterol Profile.

Observation
Element Id Observation
Definition

Group of elements for LDL Cholesterol result.

Short Display LDL Cholesterol Result
Cardinality 1..1
Alternate Names Vital Signs, Measurement, Results, Tests
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.

Invariants
Inherited by this element
dom-2RuleIf the resource is contained in another resource, it SHALL NOT contain nested Resourcescontained.contained.empty()
dom-3RuleIf the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resourcecontained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().ofType(canonical) | %resource.descendants().ofType(uri) | %resource.descendants().ofType(url))) or descendants().where(reference = '#').exists() or descendants().where(ofType(canonical) = '#').exists() or descendants().where(ofType(canonical) = '#').exists()).not()).trace('unmatched', id).empty()
dom-4RuleIf a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdatedcontained.meta.versionId.empty() and contained.meta.lastUpdated.empty()
dom-5RuleIf a resource is contained in another resource, it SHALL NOT have a security labelcontained.meta.security.empty()
dom-6GuidelineA resource should have narrative for robust managementtext.`div`.exists()
This is (only) a best practice guideline because:

When a resource has no narrative, only systems that fully understand the data can display the resource to a human safely. Including a human readable representation in the resource makes for a much more robust eco-system and cheaper handling of resources by intermediary systems. Some ecosystems restrict distribution of resources to only those systems that do fully understand the resources, and as a consequence implementers may believe that the narrative is superfluous. However experience shows that such eco-systems often open up to new participants over time.

obs-6RuledataAbsentReason SHALL only be present if Observation.value[x] is not presentdataAbsentReason.empty() or value.empty()
obs-7RuleIf Observation.component.code is the same as Observation.code, then Observation.value SHALL NOT be present (the Observation.component.value[x] holds the value).value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()
obs-8RulebodyStructure SHALL only be present if Observation.bodySite is not presentbodySite.exists() implies bodyStructure.empty()
Observation.id
Element Id Observation.id
Definition

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

Short Display Logical id of this artifact
Cardinality 0..1
Type id
Comments

Within the context of the FHIR RESTful interactions, the resource has an id except for cases like the create and conditional update. Otherwise, the use of the resouce id depends on the given use case.

Observation.meta
Element Id 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.

Short Display Metadata about the resource
Cardinality 0..1
Type Meta
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.implicitRules
Element Id 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.

Short Display A set of rules under which this content was created
Cardinality 0..1
Type uri
Is Modifier true (Reason: This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies its meaning or interpretation)
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 its narrative along with other profiles, value sets, etc.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.language
Element Id Observation.language
Definition

The base language in which the resource is written.

Short Display Language of the resource content
Cardinality 0..1
Terminology Binding IETF language tag for a human language
The codes SHALL be taken from All Languages
Type code
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).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.text
Element Id 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.

Short Display Text summary of the resource, for human interpretation
Cardinality 0..1 This element is affected by the following invariants: dom-6
Type Narrative
Alternate Names narrative, html, xhtml, display
Comments

Contained resources do not have a 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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.contained
Element Id Observation.contained
Definition

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

Short Display Contained, inline Resources
Cardinality 0..* This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
Type Resource
Alternate Names inline resources, anonymous resources, contained 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.

Observation.extension
Element Id 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 managable, 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.

Short Display Additional content defined by implementations
Cardinality 0..*
Type Extension
Alternate Names extensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.modifierExtension
Element Id 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 managable, 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).

Short Display Extensions that cannot be ignored
Cardinality 0..*
Type Extension
Is Modifier true (Reason: Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them)
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 Names extensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.identifier
Element Id Observation.identifier
Definition

A unique identifier assigned to this observation.

Short Display Business Identifier for observation
Cardinality 0..*
Type Identifier
Requirements

Allows observations to be distinguished and referenced.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.instantiates[x]
Element Id Observation.instantiates[x]
Definition

The reference to a FHIR ObservationDefinition resource that provides the definition that is adhered to in whole or in part by this Observation instance.

Short Display Instantiates FHIR ObservationDefinition
Cardinality 0..1
Type Choice of: canonical(ObservationDefinition), Reference(ObservationDefinition)
[x] Note See Choice of Datatypes for further information about how to use [x]
Comments

ObservationDefinition can be referenced by its canonical url using instantiatesCanonical, or by a name or an identifier using the appropriate sub-elements of instantiatesReference.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.basedOn
Element Id 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.

Short Display Fulfills plan, proposal or order
Cardinality 0..*
Type Reference(CarePlan)
Requirements

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

Alternate Names Fulfills
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy
Element Id Observation.triggeredBy
Definition

Identifies the observation(s) that triggered the performance of this observation.

Short Display Triggering observation(s)
Cardinality 0..*
Type BackboneElement
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.id
Element Id Observation.triggeredBy.id
Definition

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

Short Display Unique id for inter-element referencing
Cardinality 0..1 This element is affected by the following invariants: ele-1
Type string
Observation.triggeredBy.extension
Element Id Observation.triggeredBy.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 managable, 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.

Short Display Additional content defined by implementations
Cardinality 0..*
Type Extension
Alternate Names extensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.modifierExtension
Element Id Observation.triggeredBy.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 managable, 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).

Short Display Extensions that cannot be ignored even if unrecognized
Cardinality 0..*
Type Extension
Is Modifier true (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
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 Names extensions, user content, modifiers
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.observation
Element Id Observation.triggeredBy.observation
Definition

Reference to the triggering observation.

Short Display Triggering observation
Cardinality 1..1
Type Reference(Observation)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.type
Element Id Observation.triggeredBy.type
Definition

The type of trigger. Reflex | Repeat | Re-run.

Short Display reflex | repeat | re-run
Cardinality 1..1
Terminology Binding The type of TriggeredBy Observation.
The codes SHALL be taken from triggered Bytype
Type code
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.reason
Element Id Observation.triggeredBy.reason
Definition

Provides the reason why this observation was performed as a result of the observation(s) referenced.

Short Display Reason that the observation was triggered
Cardinality 0..1
Type string
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.partOf
Element Id 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.

Short Display Part of referenced event
Cardinality 0..*
Type Reference(MedicationAdministration)
Alternate Names Container
Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.status
Element Id Observation.status
Definition

The status of the result value.

Short Display registered | specimen-in-process | preliminary | final | amended | corrected | appended | cancelled | entered-in-error | unknown
Cardinality 1..1
Terminology Binding Codes providing the status of an observation.
The codes SHALL be taken from Observation Status
Type code
Is Modifier true (Reason: 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)
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category
Element Id Observation.category
Definition

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

Short Display Classification of type of observation
Cardinality 0..*
Terminology Binding Codes for high level observation categories.
The codes SHOULD be taken from Observation Category Codes
Type CodeableConcept
Requirements

Used for filtering what observations are retrieved and displayed.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code
Element Id Observation.code
Definition

LDL Cholesterol -measured or calculated per code.

Short Display LDL Cholesterol -measured or calculated per code
Cardinality 1..1 This element is affected by the following invariants: obs-7
Terminology Binding LDL Cholesterol codes - measured or calculated.
The codes SHALL be taken from L D L Codes
Type CodeableConcept
Must Support true
Requirements

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

Alternate Names Name
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.subject
Element Id Observation.subject
Definition

The patient, or group of patients, location, device, organization, procedure or practitioner this observation is about and into whose or what 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.

Short Display Who and/or what the observation is about
Cardinality 0..1
Type Reference(Patient)
Requirements

Observations have no value if you don't know who or what they're 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. The subject of an Observation may in some cases be a procedure. This supports the regulatory inspection use case where observations are captured during inspections of a procedure that is being performed (independent of any particular patient or whether patient related at all).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.focus
Element Id 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.

Short Display What the observation is about, when it is not about the subject of record
Cardinality 0..*
Type Reference(Resource)
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 http://hl7.org/fhir/StructureDefinition/observation-focusCode.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.encounter
Element Id Observation.encounter
Definition

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

Short Display Healthcare event during which this observation is made
Cardinality 0..1
Type Reference(Encounter)
Requirements

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

Alternate Names Context
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).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.effective[x]
Element Id 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.

Short Display Clinically relevant time/time-period for observation
Cardinality 0..1
Type Choice of: dateTime, Period, Timing, instant
[x] Note See Choice of Datatypes for further information about how to use [x]
Requirements

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

Alternate Names Occurrence
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.issued
Element Id 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.

Short Display Date/Time this version was made available
Cardinality 0..1
Type instant
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.performer
Element Id Observation.performer
Definition

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

Short Display Who is responsible for the observation
Cardinality 0..*
Type Reference(Practitioner)
Requirements

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x]
Element Id Observation.value[x]
Definition

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

Short Display Actual result
Cardinality 0..1 This element is affected by the following invariants: obs-7, obs-6
Type Quantity
[x] Note See Choice of Datatypes for further information about how to use [x]
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.

Comments
  • An observation may have:
    1. a single value here
    2. both a value and a set of related or component values
    3. only a set of related or component values.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Slicing This element introduces a set of slices. The slicing rules are:
  • unordered
  • Closed
  • discriminators: type:$this
Observation.value[x](valueQuantity)
Element Id Observation.value[x]:valueQuantity
Definition

LDL Cholesterol value. If a result is not available, use the comments field.

Short Display LDL Cholesterol value
Cardinality 0..1 This element is affected by the following invariants: obs-7, obs-6
Type Quantity
[x] Note See Choice of Datatypes for further information about how to use [x]
Must Support true
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.

Comments
  • An observation may have:
    1. a single value here
    2. both a value and a set of related or component values
    3. only a set of related or component values.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.dataAbsentReason
Element Id Observation.dataAbsentReason
Definition

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

Short Display Why the result value is missing
Cardinality 0..1 This element is affected by the following invariants: obs-6
Terminology Binding Codes specifying why the result (`Observation.value[x]`) is missing.
The codes SHALL be taken from Data Absent Reason; other codes may be used where these codes are not suitable
Type CodeableConcept
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.interpretation
Element Id Observation.interpretation
Definition
  • | ++ | +++ | - | -- | ---.
Short Display + | ++ | +++ | - | -- | ---
Cardinality 0..1
Terminology Binding Codes identifying interpretations of observations.
The codes SHALL be taken from Observation Interpretation Codes; other codes may be used where these codes are not suitable
Type CodeableConcept
Must Support true
Requirements

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

Alternate Names Abnormal Flag
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.note
Element Id Observation.note
Definition

Comments about result.

Short Display Comments about result
Cardinality 0..*
Type Annotation
Must Support true
Requirements

Need to be able to provide free text additional information.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.bodySite
Element Id Observation.bodySite
Definition

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

Short Display Observed body part
Cardinality 0..1 This element is affected by the following invariants: obs-8
Terminology Binding SNOMED CT Body site concepts
For example codes, see SNOMED CT Body Structures
Type CodeableConcept
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.bodyStructure
Element Id Observation.bodyStructure
Definition

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

Short Display Observed body structure
Cardinality 0..1 This element is affected by the following invariants: obs-8
Type Reference(BodyStructure)
Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.method
Element Id Observation.method
Definition

Indicates the mechanism used to perform the observation.

Short Display How it was done
Cardinality 0..1
Terminology Binding Methods for simple observations.
For example codes, see Observation Methods
Type CodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.specimen
Element Id Observation.specimen
Definition

The specimen that was used when this observation was made.

Short Display Specimen used for this observation
Cardinality 0..1
Type Reference(Specimen)
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).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
obs-9RuleIf Observation.specimen is a reference to Group, the group can only have specimens(reference.resolve().exists() and reference.resolve() is Group) implies reference.resolve().member.entity.resolve().all($this is Specimen)
Observation.device
Element Id Observation.device
Definition

A reference to the device that generates the measurements or the device settings for the device.

Short Display A reference to the device that generates the measurements or the device settings for the device
Cardinality 0..1
Type Reference(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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange
Element Id 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.

Short Display Provides guide for interpretation
Cardinality 1..1
Type BackboneElement
Must Support true
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.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
obs-3RuleMust have at least a low or a high or textlow.exists() or high.exists() or text.exists()
Observation.referenceRange.id
Element Id 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.

Short Display Unique id for inter-element referencing
Cardinality 0..1 This element is affected by the following invariants: ele-1
Type string
Observation.referenceRange.extension
Element Id 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 managable, 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.

Short Display Additional content defined by implementations
Cardinality 0..*
Type Extension
Alternate Names extensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.modifierExtension
Element Id 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 managable, 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).

Short Display Extensions that cannot be ignored even if unrecognized
Cardinality 0..*
Type Extension
Is Modifier true (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
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 Names extensions, user content, modifiers
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.low
Element Id 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).

Short Display Low Range, if relevant
Cardinality 0..0 This element is affected by the following invariants: obs-3
Type Quantity(Quantity)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.high
Element Id Observation.referenceRange.high
Definition

<3.0 mmol/L.

Short Display A fixed quantity (no comparator)
Cardinality 1..1
Type Quantity(SimpleQuantity)
Comments

Per Australian NHF Recommendations.

Fixed Value <valueQuantity xmlns="http://hl7.org/fhir">
  <value value="3.0"/>
</valueQuantity>
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
sqty-1RuleThe comparator is not used on a SimpleQuantitycomparator.empty()
qty-3RuleIf a code for the unit is present, the system SHALL also be presentcode.empty() or system.exists()
Observation.referenceRange.normalValue
Element Id Observation.referenceRange.normalValue
Definition

The value of the normal value of the reference range.

Short Display Normal value, if relevant
Cardinality 0..1
Terminology Binding Codes identifying the normal value of the observation.
The codes SHALL be taken from Observation Reference Range Normal Value Codes; other codes may be used where these codes are not suitable
Type CodeableConcept
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.type
Element Id 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.

Short Display Reference range qualifier
Cardinality 0..0
Terminology Binding Code for the meaning of a reference range.
The codes SHOULD be taken from Observation Reference Range Meaning Codes
Type CodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.appliesTo
Element Id 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.

Short Display Reference range population
Cardinality 0..0
Terminology Binding Codes identifying the population the reference range applies to.
For example codes, see Observation Reference Range Applies To Codes
Type CodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.age
Element Id 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.

Short Display Applicable age range, if relevant
Cardinality 0..0
Type Range
Requirements

Some analytes vary greatly over age.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.text
Element Id 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".

Short Display Text based reference range in an observation
Cardinality 0..1 This element is affected by the following invariants: obs-3
Type markdown
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.hasMember
Element Id 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.

Short Display Related resource that belongs to the Observation group
Cardinality 0..0
Type Reference(Observation)
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.derivedFrom
Element Id 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.

Short Display Related resource from which the observation is made
Cardinality 0..0
Type Reference(DocumentReference)
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component
Element Id 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.

Short Display Component results
Cardinality 0..* This element is affected by the following invariants: obs-7
Type BackboneElement
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, reference range, dataAbsentReason, and interpretation can differ between the components and are not inherited; these should be provided if appropriate.

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.id
Element Id 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.

Short Display Unique id for inter-element referencing
Cardinality 0..1 This element is affected by the following invariants: ele-1
Type string
Observation.component.extension
Element Id 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 managable, 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.

Short Display Additional content defined by implementations
Cardinality 0..*
Type Extension
Alternate Names extensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.modifierExtension
Element Id 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 managable, 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).

Short Display Extensions that cannot be ignored even if unrecognized
Cardinality 0..*
Type Extension
Is Modifier true (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
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 Names extensions, user content, modifiers
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.code
Element Id Observation.component.code
Definition

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

Short Display Type of component observation (code / type)
Cardinality 1..1 This element is affected by the following invariants: obs-7
Terminology Binding Codes identifying names of simple observations.
For example codes, see LOINC Codes
Type CodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.value[x]
Element Id Observation.component.value[x]
Definition

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

Short Display Actual component result
Cardinality 0..1
Type Choice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period, Attachment, Reference(MolecularSequence)
[x] Note See Choice of Datatypes for further information about how to use [x]
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.

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 the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.dataAbsentReason
Element Id Observation.component.dataAbsentReason
Definition

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

Short Display Why the component result value is missing
Cardinality 0..1
Terminology Binding Codes specifying why the result (`Observation.value[x]`) is missing.
The codes SHALL be taken from Data Absent Reason; other codes may be used where these codes are not suitable
Type CodeableConcept
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.interpretation
Element Id Observation.component.interpretation
Definition

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

Short Display High, low, normal, etc
Cardinality 0..*
Terminology Binding Codes identifying interpretations of observations.
The codes SHALL be taken from Observation Interpretation Codes; other codes may be used where these codes are not suitable
Type CodeableConcept
Requirements

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

Alternate Names Abnormal Flag
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.referenceRange
Element Id Observation.component.referenceRange
Definition

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

Short Display Provides guide for interpretation of component result value
Cardinality 0..*
Type See ttp://hl7.org/fhir/StructureDefinition/Observation#Observation.referenceRange
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.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())