AU Base Implementation Guide
4.2.1-preview - Preview Australia flag

This page is part of the Australian Base IG (v4.2.1-preview: QA Preview) based on FHIR (HL7® FHIR® Standard) R4. The current version which supersedes this version is 4.1.0. For a full list of available versions, see the Directory of published versions

Resource Profile: AUBaseDiagnosticImagingResult - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 1

Definitions for the au-imagingresult resource profile.

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

0. Observation
Definition

A diagnostic imaging examination result for a patient. This observation may be a simple examination or a study series.

ShortA imaging examination result in an Australian healthcare context
Invariantsinv-obs-0: An imaging result shall at least have value or data absent reason or a child observation with a value or data absent reason (value.exists() or dataAbsentReason.exists() or hasMember.exists() or component.value.exists() or component.dataAbsentReason.exists())
2. Observation.category
ShortRelevant diagnostic imaging category: service, modality and anatomic region
Comments

A category denoting diagnostic imaging service identifies the type of report and supports macro handling of requests is required. A second category to provide the modality should be provided where possible; a value set to support this categorisation is not yet available. A third category to provide the anatomic region of interest should be provided where possible.

Control1..?
SlicingThis element introduces a set of slices on Observation.category. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ coding.system
  • value @ coding.code
  • 4. Observation.category:diagImg
    Slice NamediagImg
    ShortObservation generated by imaging
    Control1..1
    6. Observation.category:diagImg.coding
    Control1..?
    8. Observation.category:diagImg.coding.system
    Control1..?
    Fixed Valuehttp://terminology.hl7.org/CodeSystem/observation-category
    10. Observation.category:diagImg.coding.code
    Control1..?
    Fixed Valueimaging
    12. Observation.category:anatomicRegionOfInterest
    Slice NameanatomicRegionOfInterest
    ShortAnatomic Region Of Interest
    BindingUnless not suitable, these codes SHALL be taken from Imaging Anatomic Region Of Interest .
    (extensible to https://healthterminologies.gov.au/fhir/ValueSet/imaging-anatomic-region-of-interest-1)
    14. Observation.category:anatomicRegionOfInterest.coding
    16. Observation.category:anatomicRegionOfInterest.coding.system
    Control1..?
    Fixed Valuehttp://snomed.info/sct
    18. Observation.code
    ShortDiagnostic imaging examination or study
    BindingThe codes SHOULD be taken from Imaging Procedure .
    (preferred to https://healthterminologies.gov.au/fhir/ValueSet/imaging-procedure-1)
    20. Observation.subject
    Control1..?
    TypeReference(Patient)
    22. Observation.effective[x]
    ShortTime of diagnostic imaging examination
    Control1..?
    TypeChoice of: dateTime, Period, Timing, instant
    [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
    24. Observation.value[x]
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    26. Observation.dataAbsentReason
    28. Observation.bodySite
    BindingThe codes SHOULD be taken from Body Site .
    (preferred to https://healthterminologies.gov.au/fhir/ValueSet/body-site-1)
    30. Observation.bodySite.extension
    SlicingThis element introduces a set of slices on Observation.bodySite.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
    • value @ url
    • 32. Observation.bodySite.extension:bodySite
      Slice NamebodySite
      Control0..1
      TypeExtension(BodyStructure Reference) (Extension Type: Reference(BodyStructure))
      34. Observation.hasMember
      ShortIndividual examinations in a group or study series
      TypeReference(AU Base Diagnostic Result, AU Base Diagnostic Imaging Result)
      36. Observation.component
      ShortIndividual examinations in a group or study series
      38. Observation.component.code
      ShortDiagnostic imaging examination or study
      BindingThe codes SHOULD be taken from Imaging Procedure .
      (preferred to https://healthterminologies.gov.au/fhir/ValueSet/imaging-procedure-1)
      40. Observation.component.value[x]
      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
      42. Observation.component.dataAbsentReason

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

      0. Observation
      Definition

      A diagnostic imaging examination result for a patient. This observation may be a simple examination or a study series.


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

      ShortA imaging examination result in an Australian healthcare contextMeasurements 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())
      inv-obs-0: An imaging result shall at least have value or data absent reason or a child observation with a value or data absent reason (value.exists() or dataAbsentReason.exists() or hasMember.exists() or component.value.exists() or component.dataAbsentReason.exists())
      obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
      obs-7: If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty())
      2. Observation.implicitRules
      Definition

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

      ShortA set of rules under which this content was created
      Comments

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

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

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

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

      ShortExtensions that cannot be ignored
      Comments

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

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

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

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

      The status of the result value.

      Shortregistered | preliminary | final | amended +
      Comments

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

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

      Codes providing the status of an observation.

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

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

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

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

      ShortRelevant diagnostic imaging category: service, modality and anatomic regionClassification of type of observation
      Comments

      A category denoting diagnostic imaging service identifies the type of report and supports macro handling of requests is required. A second category to provide the modality should be provided where possible; a value set to support this categorisation is not yet available. A third category to provide the anatomic region of interest should be provided where possible.


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

      Control10..*
      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
      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()))
      SlicingThis element introduces a set of slices on Observation.category. The slices areUnordered and Open, and can be differentiated using the following discriminators:
      • value @ coding.system
      • value @ coding.code
      • 10. Observation.category:diagImg
        Slice NamediagImg
        Definition

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

        ShortObservation generated by imagingClassification 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.

        Control10..1*
        BindingThe codes SHOULD be taken from ObservationCategoryCodeshttp://hl7.org/fhir/ValueSet/observation-category
        (preferred to http://hl7.org/fhir/ValueSet/observation-category)

        Codes for high level observation categories.

        TypeCodeableConcept
        Is Modifierfalse
        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()))
        12. Observation.category:diagImg.coding
        Definition

        A reference to a code defined by a terminology system.

        ShortCode defined by a terminology system
        Comments

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

        Control10..*
        TypeCoding
        Is Modifierfalse
        Summarytrue
        Requirements

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

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

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

        ShortIdentity of the terminology system
        Comments

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

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

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

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

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

        ShortSymbol in syntax defined by the system
        Control10..1
        Typecode
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Summarytrue
        Requirements

        Need to refer to a particular code in the system.

        Fixed Valueimaging
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        18. Observation.category:anatomicRegionOfInterest
        Slice NameanatomicRegionOfInterest
        Definition

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

        ShortAnatomic Region Of InterestClassification 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..*
        BindingUnless not suitable, these codes SHALL be taken from The codes SHOULD be taken from Imaging Anatomic Region Of Interest .http://hl7.org/fhir/ValueSet/observation-category
        (extensible to https://healthterminologies.gov.au/fhir/ValueSet/imaging-anatomic-region-of-interest-1)
        TypeCodeableConcept
        Is Modifierfalse
        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()))
        20. Observation.code
        Definition

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

        ShortDiagnostic imaging examination or studyType 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
        BindingThe codes SHOULD be taken from For example codes, see Imaging Procedure .http://hl7.org/fhir/ValueSet/observation-codes
        (preferred to https://healthterminologies.gov.au/fhir/ValueSet/imaging-procedure-1)
        TypeCodeableConcept
        Is Modifierfalse
        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()))
        22. Observation.subject
        Definition

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

        ShortWho and/or what the observation is about
        Comments

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

        Control10..1
        TypeReference(Patient, Group, Device, Location)
        Is Modifierfalse
        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()))
        24. 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.

        ShortTime of diagnostic imaging examinationClinically relevant time/time-period for observation
        Comments

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

        Control10..1
        TypeChoice of: dateTime, Period, Timing, instant
        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        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.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, inv-obs-0
        TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Summarytrue
        Requirements

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

        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        28. 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, inv-obs-0
        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
        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()))
        30. 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
        BindingThe codes SHOULD be taken from For example codes, see Body Site .http://hl7.org/fhir/ValueSet/body-site
        (preferred to https://healthterminologies.gov.au/fhir/ValueSet/body-site-1)
        TypeCodeableConcept
        Is Modifierfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        32. Observation.bodySite.extension
        Definition

        An Extension


        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.

        ShortExtensionAdditional 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.bodySite.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
        • value @ url
        • 34. Observation.bodySite.extension:bodySite
          Slice NamebodySite
          Definition

          Record details about the anatomical location of a specimen or body part. This resource may be used when a coded concept does not provide the necessary detail needed for the use case.

          ShortTarget anatomic location or structure
          Control0..1
          TypeExtension(BodyStructure Reference) (Extension Type: Reference(BodyStructure))
          Is Modifierfalse
          Summaryfalse
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
          36. 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.

          ShortIndividual examinations in a group or study seriesRelated 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..*
          This element is affected by the following invariants: inv-obs-0
          TypeReference(AU Base Diagnostic Result, AU Base Diagnostic Imaging Result, Observation, QuestionnaireResponse, MolecularSequence)
          Is Modifierfalse
          Summarytrue
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          38. 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.

          ShortIndividual examinations in a group or study seriesComponent 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()))
          40. 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())
          42. Observation.component.code
          Definition

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

          ShortDiagnostic imaging examination or studyType 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
          BindingThe codes SHOULD be taken from For example codes, see Imaging Procedure .http://hl7.org/fhir/ValueSet/observation-codes
          (preferred to https://healthterminologies.gov.au/fhir/ValueSet/imaging-procedure-1)
          TypeCodeableConcept
          Is Modifierfalse
          Summarytrue
          Requirements

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

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          44. 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
          This element is affected by the following invariants: inv-obs-0
          TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
          [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
          Is Modifierfalse
          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
          Summarytrue
          Requirements

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

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          46. 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, inv-obs-0
          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
          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()))

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

          0. Observation
          Definition

          A diagnostic imaging examination result for a patient. This observation may be a simple examination or a study series.

          ShortA imaging examination result in an Australian healthcare context
          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())
          inv-obs-0: An imaging result shall at least have value or data absent reason or a child observation with a value or data absent reason (value.exists() or dataAbsentReason.exists() or hasMember.exists() or component.value.exists() or component.dataAbsentReason.exists())
          2. Observation.id
          Definition

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

          ShortLogical id of this artifact
          Comments

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

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

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

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

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

          ShortA set of rules under which this content was created
          Comments

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

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

          The base language in which the resource is written.

          ShortLanguage of the resource content
          Comments

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

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

          A human language.

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

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

          ShortText summary of the resource, for human interpretation
          Comments

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

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

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

          ShortContained, inline Resources
          Comments

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

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

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

          ShortAdditional content defined by implementations
          Comments

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

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

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

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

          ShortExtensions that cannot be ignored
          Comments

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

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

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

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

          A unique identifier assigned to this observation.

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

          Allows observations to be distinguished and referenced.

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

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

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

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

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

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

          ShortPart of referenced event
          Comments

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

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

          The status of the result value.

          Shortregistered | preliminary | final | amended +
          Comments

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

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

          Codes providing the status of an observation.

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

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

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

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

          ShortRelevant diagnostic imaging category: service, modality and anatomic region
          Comments

          A category denoting diagnostic imaging service identifies the type of report and supports macro handling of requests is required. A second category to provide the modality should be provided where possible; a value set to support this categorisation is not yet available. A third category to provide the anatomic region of interest should be provided where possible.

          Control1..*
          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
          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()))
          SlicingThis element introduces a set of slices on Observation.category. The slices areUnordered and Open, and can be differentiated using the following discriminators:
          • value @ coding.system
          • value @ coding.code
          • 28. Observation.category:diagImg
            Slice NamediagImg
            Definition

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

            ShortObservation generated by imaging
            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.

            Control1..1
            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
            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()))
            30. Observation.category:diagImg.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
            32. Observation.category:diagImg.extension
            Definition

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

            ShortAdditional content defined by implementations
            Comments

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

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

              A reference to a code defined by a terminology system.

              ShortCode defined by a terminology system
              Comments

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

              Control1..*
              TypeCoding
              Is Modifierfalse
              Summarytrue
              Requirements

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

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

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

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

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

              ShortAdditional content defined by implementations
              Comments

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

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

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

                ShortIdentity of the terminology system
                Comments

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

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

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

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

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

                ShortVersion of the system - if relevant
                Comments

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

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

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

                ShortSymbol in syntax defined by the system
                Control1..1
                Typecode
                Is Modifierfalse
                Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                Summarytrue
                Requirements

                Need to refer to a particular code in the system.

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

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

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

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

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

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

                ShortIf this coding was chosen directly by the user
                Comments

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

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

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

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

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

                ShortPlain text representation of the concept
                Comments

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

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

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

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

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

                ShortAnatomic Region Of Interest
                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..*
                BindingUnless not suitable, these codes SHALL be taken from Imaging Anatomic Region Of Interest .
                (extensible to https://healthterminologies.gov.au/fhir/ValueSet/imaging-anatomic-region-of-interest-1)
                TypeCodeableConcept
                Is Modifierfalse
                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()))
                54. Observation.category:anatomicRegionOfInterest.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
                56. Observation.category:anatomicRegionOfInterest.extension
                Definition

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

                ShortAdditional content defined by implementations
                Comments

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

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

                  A reference to a code defined by a terminology system.

                  ShortCode defined by a terminology system
                  Comments

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

                  Control0..*
                  TypeCoding
                  Is Modifierfalse
                  Summarytrue
                  Requirements

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

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

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

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

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

                  ShortAdditional content defined by implementations
                  Comments

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

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

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

                    ShortIdentity of the terminology system
                    Comments

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

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

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

                    Fixed Valuehttp://snomed.info/sct
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    66. Observation.category:anatomicRegionOfInterest.coding.version
                    Definition

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

                    ShortVersion of the system - if relevant
                    Comments

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

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

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

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

                    Need to refer to a particular code in the system.

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

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

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

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

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

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

                    ShortIf this coding was chosen directly by the user
                    Comments

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

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

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

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

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

                    ShortPlain text representation of the concept
                    Comments

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

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

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

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

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

                    ShortDiagnostic imaging examination or study
                    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
                    BindingThe codes SHOULD be taken from Imaging Procedure .
                    (preferred to https://healthterminologies.gov.au/fhir/ValueSet/imaging-procedure-1)
                    TypeCodeableConcept
                    Is Modifierfalse
                    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()))
                    78. Observation.subject
                    Definition

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

                    ShortWho and/or what the observation is about
                    Comments

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

                    Control1..1
                    TypeReference(Patient)
                    Is Modifierfalse
                    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()))
                    80. 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()))
                    82. 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()))
                    84. 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.

                    ShortTime of diagnostic imaging examination
                    Comments

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

                    Control1..1
                    TypeChoice of: dateTime, Period
                    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    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()))
                    86. Observation.issued
                    Definition

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

                    ShortDate/Time this version was made available
                    Comments

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

                    Control0..1
                    Typeinstant
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    88. 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()))
                    90. 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, inv-obs-0
                    TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
                    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Requirements

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

                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    92. 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, inv-obs-0
                    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()))
                    94. 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
                    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()))
                    96. 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()))
                    98. 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
                    BindingThe codes SHOULD be taken from Body Site .
                    (preferred to https://healthterminologies.gov.au/fhir/ValueSet/body-site-1)
                    TypeCodeableConcept
                    Is Modifierfalse
                    Summaryfalse
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    100. Observation.bodySite.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
                    102. Observation.bodySite.extension
                    Definition

                    An Extension

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

                      Record details about the anatomical location of a specimen or body part. This resource may be used when a coded concept does not provide the necessary detail needed for the use case.

                      ShortTarget anatomic location or structure
                      Control0..1
                      TypeExtension(BodyStructure Reference) (Extension Type: Reference(BodyStructure))
                      Is Modifierfalse
                      Summaryfalse
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                      106. Observation.bodySite.coding
                      Definition

                      A reference to a code defined by a terminology system.

                      ShortCode defined by a terminology system
                      Comments

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

                      Control0..*
                      TypeCoding
                      Is Modifierfalse
                      Summarytrue
                      Requirements

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

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

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

                      ShortPlain text representation of the concept
                      Comments

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

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

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

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

                      Indicates the mechanism used to perform the observation.

                      ShortHow it was done
                      Comments

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

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

                      Methods for simple observations.

                      TypeCodeableConcept
                      Is Modifierfalse
                      Summaryfalse
                      Requirements

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

                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      112. 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()))
                      114. 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()))
                      116. 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
                      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())
                      118. 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
                      120. 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())
                      122. 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())
                      124. 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()))
                      126. 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()))
                      128. 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()))
                      130. 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()))
                      132. 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()))
                      134. 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()))
                      136. 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.

                      ShortIndividual examinations in a group or study series
                      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..*
                      This element is affected by the following invariants: inv-obs-0
                      TypeReference(AU Base Diagnostic Result, AU Base Diagnostic Imaging Result)
                      Is Modifierfalse
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      138. 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()))
                      140. 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.

                      ShortIndividual examinations in a group or study series
                      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()))
                      142. 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
                      144. 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())
                      146. 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())
                      148. Observation.component.code
                      Definition

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

                      ShortDiagnostic imaging examination or study
                      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
                      BindingThe codes SHOULD be taken from Imaging Procedure .
                      (preferred to https://healthterminologies.gov.au/fhir/ValueSet/imaging-procedure-1)
                      TypeCodeableConcept
                      Is Modifierfalse
                      Summarytrue
                      Requirements

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

                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      150. 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
                      This element is affected by the following invariants: inv-obs-0
                      TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
                      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Summarytrue
                      Requirements

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

                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      152. 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, inv-obs-0
                      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()))
                      154. 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()))
                      156. 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()))