LOINC – IVD Test Code (LIVD) Mapping
1.0.0 - STU 1 International flag

LOINC – IVD Test Code (LIVD) Mapping, published by HL7 International / Orders and Observations. This guide is not an authorized publication; it is the continuous build for version 1.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/livd/ and changes regularly. See the Directory of published versions

Resource Profile: LIVDObservationDefinition - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 2

Definitions for the observationdefinition-uv-livd resource profile.

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

0. ObservationDefinition
Definition

Set of definitional characteristics for a kind of observation or measurement produced or consumed by an orderable health care service.

ShortLIVDObservationDefinitionDefinition of an observation
Comments

An instance of this resource informs the consumer of a health-related service (such as a lab diagnostic test or panel) about how the observations used or produced by this service will look like.

Control0..*
Is Modifierfalse
Must Supportfalse
Summaryfalse
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())
2. ObservationDefinition.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. ObservationDefinition.extension
Definition

An Extension


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.

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.

Control10..*
TypeExtension
Is Modifierfalse
Must Supporttrue
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 ObservationDefinition.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ url
  • 6. ObservationDefinition.extension:ObservationDefinitionDevice
    Slice NameObservationDefinitionDevice
    Definition

    Add a reference from the ObservationDefinition to the Device.

    ShortLIVD Device
    Control1..*
    This element is affected by the following invariants: ele-1
    TypeExtension(LIVD Device) (Extension Type: Reference)
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    8. ObservationDefinition.extension:ObservationDefinitionVendorReferenceIdentifier
    Slice NameObservationDefinitionVendorReferenceIdentifier
    Definition

    Add a vendor reference identifier to ObservationDefinition.

    ShortLIVD Vendor Reference Identifier
    Comments

    Provides an alternate reference identifier by which the IVD Test is known. Only the identifier.value is required.

    Control0..1
    This element is affected by the following invariants: ele-1
    TypeExtension(LIVD Vendor Reference Identifier) (Extension Type: Identifier)
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
    10. ObservationDefinition.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())
    12. ObservationDefinition.category
    Definition

    A code that classifies the general type of observation.

    ShortCategory 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.


    This element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used for one instance of ObservationDefinition. The level of granularity is defined by the category concepts in the value set.

    Control0..0*
    BindingFor example codes, see ObservationCategoryCodeshttp://hl7.org/fhir/ValueSet/observation-category
    (example to http://hl7.org/fhir/ValueSet/observation-category)

    Codes for high level observation categories.

    TypeCodeableConcept
    Is Modifierfalse
    Must Supportfalse
    Summarytrue
    Requirements

    Used for filtering what observations are retrieved and displayed.


    Used for filtering what kinds of observations are retrieved and displayed.

    Alternate NamesClass of observation
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    14. ObservationDefinition.code
    Definition

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

    ShortType of observation (code / type)
    Comments

    Contains both the IVD Test Code and Name of the analyte.

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

    Codes identifying names of simple observations.

    TypeCodeableConcept
    Is Modifierfalse
    Must Supporttrue
    Summarytrue
    Requirements

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

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

    A unique identifier assigned to this ObservationDefinition artifact.

    ShortBusiness identifier for this ObservationDefinition instance
    NoteThis is a business identifier, not a resource identifier (see discussion)
    Control0..*
    TypeIdentifier
    Is Modifierfalse
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    18. ObservationDefinition.permittedDataType
    Definition

    data type allowed for the result of the observation.


    The data types allowed for the value element of the instance observations conforming to this ObservationDefinition.

    ShortQuantity | CodeableConcept | string | boolean | integer | Range | Ratio | SampledData | time | dateTime | Period
    Control0..1*
    BindingThe codes SHALL be taken from ObservationDataTypehttp://hl7.org/fhir/ValueSet/permitted-data-type|4.0.1
    (required to http://hl7.org/fhir/ValueSet/permitted-data-type|4.0.1)

    Permitted data type for observation value.

    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Example<br/><b>General</b>:CodeableConcept
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    20. ObservationDefinition.multipleResultsAllowed
    Definition

    Multiple results allowed for this kind of observation.


    Multiple results allowed for observations conforming to this ObservationDefinition.

    ShortMultiple results allowed
    Comments

    An example of observation allowing multiple results is "bacteria identified by culture". Conversely, the measurement of a potassium level allows a single result.

    Control0..01
    Typeboolean
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summaryfalse
    Example<br/><b>General</b>:true
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    22. ObservationDefinition.method
    Definition

    The method or technique used to perform the observation.

    ShortMethod used to produce the observation
    Comments

    Only used if not implicit in observation code.

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

    Methods for simple observations.

    TypeCodeableConcept
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Requirements

    In some cases, method can impact results.

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

    The preferred name to be used when reporting the results of this observation.


    The preferred name to be used when reporting the results of observations conforming to this ObservationDefinition.

    ShortPreferred report name
    Control0..01
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    26. ObservationDefinition.quantitativeDetails
    Definition

    Characteristics for quantitative results of this observation.

    ShortCharacteristics of quantitative results
    Control0..1
    TypeBackboneElement
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    28. ObservationDefinition.quantitativeDetails.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())
    30. ObservationDefinition.quantitativeDetails.customaryUnit
    Definition

    Customary unit used to report quantitative results of this observation.


    Customary unit used to report quantitative results of observations conforming to this ObservationDefinition.

    ShortCustomary unit for quantitative results
    Control0..1
    BindingUnless not suitable, these codes SHALL be taken from UCUMCodeshttp://hl7.org/fhir/ValueSet/ucum-units
    (extensible to http://hl7.org/fhir/ValueSet/ucum-units)

    Codes identifying units of measure.

    TypeCodeableConcept
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    32. ObservationDefinition.quantitativeDetails.unit
    Definition

    SI unit used to report quantitative results of this observation.


    SI unit used to report quantitative results of observations conforming to this ObservationDefinition.

    ShortSI unit for quantitative results
    Control0..1
    BindingUnless not suitable, these codes SHALL be taken from UCUMCodeshttp://hl7.org/fhir/ValueSet/ucum-units
    (extensible to http://hl7.org/fhir/ValueSet/ucum-units)

    Codes identifying units of measure.

    TypeCodeableConcept
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    34. ObservationDefinition.quantitativeDetails.conversionFactor
    Definition

    Factor for converting value expressed with SI unit to value expressed with customary unit.

    ShortSI unit to customary unit conversion factorSI to Customary unit conversion factor
    Control0..1
    Typedecimal
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    36. ObservationDefinition.quantitativeDetails.decimalPrecision
    Definition

    number of digits after decimal separator when the results of this observation are of type Quantity.


    Number of digits after decimal separator when the results of such observations are of type Quantity.

    ShortDecimal precision of observation quantitative results
    Control0..1
    Typeinteger
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    38. ObservationDefinition.qualifiedInterval
    Definition

    Reference range for ordinal and continuous observations.


    Multiple ranges of results qualified by different contexts for ordinal or continuous observations conforming to this ObservationDefinition.

    ShortQualified range for continuous and ordinal observation results
    Control0..0*
    TypeBackboneElement
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Requirements

    multiple reference ranges, for different patient contexts.

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

    The set of valid coded results for the observation.


    The set of valid coded results for the observations conforming to this ObservationDefinition.

    ShortValue set of valid coded values for the observations conforming to this ObservationDefinition
    Control0..1
    TypeReference(ValueSet)
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    51. ObservationDefinition.normalCodedValueSet
    Definition

    The set of normal coded results for the observation.


    The set of normal coded results for the observations conforming to this ObservationDefinition.

    ShortValue set of normal coded values for the observations conforming to this ObservationDefinition
    Control0..01
    TypeReference(ValueSet)
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    53. ObservationDefinition.abnormalCodedValueSet
    Definition

    The set of abnormal coded results for the observation.


    The set of abnormal coded results for the observation conforming to this ObservationDefinition.

    ShortValue set of abnormal coded values for the observations conforming to this ObservationDefinition
    Control0..01
    TypeReference(ValueSet)
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    55. ObservationDefinition.criticalCodedValueSet
    Definition

    The set of critical coded results for the observation.


    The set of critical coded results for the observation conforming to this ObservationDefinition.

    ShortValue set of critical coded values for the observations conforming to this ObservationDefinition
    Control0..01
    TypeReference(ValueSet)
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    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 foundhere

    0. ObservationDefinition
    ShortLIVDObservationDefinition
    Must Supportfalse
    2. ObservationDefinition.extension
    Control1..?
    Must Supporttrue
    SlicingThis element introduces a set of slices on ObservationDefinition.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
    • value @ url
    • 4. ObservationDefinition.extension:ObservationDefinitionDevice
      Slice NameObservationDefinitionDevice
      Control1..*
      TypeExtension(LIVD Device) (Extension Type: Reference)
      Must Supporttrue
      6. ObservationDefinition.extension:ObservationDefinitionVendorReferenceIdentifier
      Slice NameObservationDefinitionVendorReferenceIdentifier
      Comments

      Provides an alternate reference identifier by which the IVD Test is known. Only the identifier.value is required.

      Control0..1
      TypeExtension(LIVD Vendor Reference Identifier) (Extension Type: Identifier)
      Must Supporttrue
      8. ObservationDefinition.category
      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..0
      Must Supportfalse
      Requirements

      Used for filtering what observations are retrieved and displayed.

      10. ObservationDefinition.code
      Comments

      Contains both the IVD Test Code and Name of the analyte.

      Must Supporttrue
      12. ObservationDefinition.identifier
      NoteThis is a business identifier, not a resource identifier (see discussion)
      Must Supporttrue
      14. ObservationDefinition.permittedDataType
      Definition

      data type allowed for the result of the observation.

      Control0..1
      Must Supporttrue
      16. ObservationDefinition.multipleResultsAllowed
      Definition

      Multiple results allowed for this kind of observation.

      Control0..0
      Must Supportfalse
      18. ObservationDefinition.method
      Must Supporttrue
      20. ObservationDefinition.preferredReportName
      Definition

      The preferred name to be used when reporting the results of this observation.

      Control0..0
      Must Supportfalse
      22. ObservationDefinition.quantitativeDetails
      Must Supporttrue
      24. ObservationDefinition.quantitativeDetails.customaryUnit
      Definition

      Customary unit used to report quantitative results of this observation.

      Must Supporttrue
      26. ObservationDefinition.quantitativeDetails.unit
      Definition

      SI unit used to report quantitative results of this observation.

      Must Supporttrue
      28. ObservationDefinition.quantitativeDetails.conversionFactor
      ShortSI unit to customary unit conversion factor
      Must Supporttrue
      30. ObservationDefinition.quantitativeDetails.decimalPrecision
      Definition

      number of digits after decimal separator when the results of this observation are of type Quantity.

      Must Supporttrue
      32. ObservationDefinition.qualifiedInterval
      Definition

      Reference range for ordinal and continuous observations.

      Control0..0
      Must Supportfalse
      Requirements

      multiple reference ranges, for different patient contexts.

      42. ObservationDefinition.validCodedValueSet
      Definition

      The set of valid coded results for the observation.

      Must Supporttrue
      44. ObservationDefinition.normalCodedValueSet
      Definition

      The set of normal coded results for the observation.

      Control0..0
      Must Supportfalse
      46. ObservationDefinition.abnormalCodedValueSet
      Definition

      The set of abnormal coded results for the observation.

      Control0..0
      Must Supportfalse
      48. ObservationDefinition.criticalCodedValueSet
      Definition

      The set of critical coded results for the observation.

      Control0..0
      Must Supportfalse

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

      0. ObservationDefinition
      Definition

      Set of definitional characteristics for a kind of observation or measurement produced or consumed by an orderable health care service.

      ShortLIVDObservationDefinition
      Comments

      An instance of this resource informs the consumer of a health-related service (such as a lab diagnostic test or panel) about how the observations used or produced by this service will look like.

      Control0..*
      Is Modifierfalse
      Must Supportfalse
      Summaryfalse
      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())
      2. ObservationDefinition.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. ObservationDefinition.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. ObservationDefinition.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. ObservationDefinition.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. ObservationDefinition.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. ObservationDefinition.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. ObservationDefinition.extension
      Definition

      An Extension

      ShortExtension
      Control1..*
      TypeExtension
      Is Modifierfalse
      Must Supporttrue
      Summaryfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      SlicingThis element introduces a set of slices on ObservationDefinition.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
      • value @ url
      • 16. ObservationDefinition.extension:ObservationDefinitionDevice
        Slice NameObservationDefinitionDevice
        Definition

        Add a reference from the ObservationDefinition to the Device.

        ShortLIVD Device
        Control1..*
        This element is affected by the following invariants: ele-1
        TypeExtension(LIVD Device) (Extension Type: Reference)
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
        18. ObservationDefinition.extension:ObservationDefinitionVendorReferenceIdentifier
        Slice NameObservationDefinitionVendorReferenceIdentifier
        Definition

        Add a vendor reference identifier to ObservationDefinition.

        ShortLIVD Vendor Reference Identifier
        Comments

        Provides an alternate reference identifier by which the IVD Test is known. Only the identifier.value is required.

        Control0..1
        This element is affected by the following invariants: ele-1
        TypeExtension(LIVD Vendor Reference Identifier) (Extension Type: Identifier)
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
        20. ObservationDefinition.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())
        22. ObservationDefinition.category
        Definition

        A code that classifies the general type of observation.

        ShortCategory 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..0
        BindingFor example codes, see ObservationCategoryCodes
        (example to http://hl7.org/fhir/ValueSet/observation-category)

        Codes for high level observation categories.

        TypeCodeableConcept
        Is Modifierfalse
        Must Supportfalse
        Summarytrue
        Requirements

        Used for filtering what observations are retrieved and displayed.

        Alternate NamesClass of observation
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        24. ObservationDefinition.code
        Definition

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

        ShortType of observation (code / type)
        Comments

        Contains both the IVD Test Code and Name of the analyte.

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

        Codes identifying names of simple observations.

        TypeCodeableConcept
        Is Modifierfalse
        Must Supporttrue
        Summarytrue
        Requirements

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

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

        A unique identifier assigned to this ObservationDefinition artifact.

        ShortBusiness identifier for this ObservationDefinition instance
        NoteThis is a business identifier, not a resource identifier (see discussion)
        Control0..*
        TypeIdentifier
        Is Modifierfalse
        Must Supporttrue
        Summarytrue
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        28. ObservationDefinition.permittedDataType
        Definition

        data type allowed for the result of the observation.

        ShortQuantity | CodeableConcept | string | boolean | integer | Range | Ratio | SampledData | time | dateTime | Period
        Control0..1
        BindingThe codes SHALL be taken from ObservationDataType
        (required to http://hl7.org/fhir/ValueSet/permitted-data-type|4.0.1)

        Permitted data type for observation value.

        Typecode
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Must Supporttrue
        Summaryfalse
        Example<br/><b>General</b>:CodeableConcept
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        30. ObservationDefinition.multipleResultsAllowed
        Definition

        Multiple results allowed for this kind of observation.

        ShortMultiple results allowed
        Comments

        An example of observation allowing multiple results is "bacteria identified by culture". Conversely, the measurement of a potassium level allows a single result.

        Control0..0
        Typeboolean
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Must Supportfalse
        Summaryfalse
        Example<br/><b>General</b>:true
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        32. ObservationDefinition.method
        Definition

        The method or technique used to perform the observation.

        ShortMethod used to produce the observation
        Comments

        Only used if not implicit in observation code.

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

        Methods for simple observations.

        TypeCodeableConcept
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Requirements

        In some cases, method can impact results.

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

        The preferred name to be used when reporting the results of this observation.

        ShortPreferred report name
        Control0..0
        Typestring
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Must Supportfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        36. ObservationDefinition.quantitativeDetails
        Definition

        Characteristics for quantitative results of this observation.

        ShortCharacteristics of quantitative results
        Control0..1
        TypeBackboneElement
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        38. ObservationDefinition.quantitativeDetails.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
        40. ObservationDefinition.quantitativeDetails.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())
        42. ObservationDefinition.quantitativeDetails.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())
        44. ObservationDefinition.quantitativeDetails.customaryUnit
        Definition

        Customary unit used to report quantitative results of this observation.

        ShortCustomary unit for quantitative results
        Control0..1
        BindingUnless not suitable, these codes SHALL be taken from UCUMCodes
        (extensible to http://hl7.org/fhir/ValueSet/ucum-units)

        Codes identifying units of measure.

        TypeCodeableConcept
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        46. ObservationDefinition.quantitativeDetails.unit
        Definition

        SI unit used to report quantitative results of this observation.

        ShortSI unit for quantitative results
        Control0..1
        BindingUnless not suitable, these codes SHALL be taken from UCUMCodes
        (extensible to http://hl7.org/fhir/ValueSet/ucum-units)

        Codes identifying units of measure.

        TypeCodeableConcept
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        48. ObservationDefinition.quantitativeDetails.conversionFactor
        Definition

        Factor for converting value expressed with SI unit to value expressed with customary unit.

        ShortSI unit to customary unit conversion factor
        Control0..1
        Typedecimal
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        50. ObservationDefinition.quantitativeDetails.decimalPrecision
        Definition

        number of digits after decimal separator when the results of this observation are of type Quantity.

        ShortDecimal precision of observation quantitative results
        Control0..1
        Typeinteger
        Is Modifierfalse
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        52. ObservationDefinition.qualifiedInterval
        Definition

        Reference range for ordinal and continuous observations.

        ShortQualified range for continuous and ordinal observation results
        Control0..0
        TypeBackboneElement
        Is Modifierfalse
        Must Supportfalse
        Summaryfalse
        Requirements

        multiple reference ranges, for different patient contexts.

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

        The set of valid coded results for the observation.

        ShortValue set of valid coded values for the observations conforming to this ObservationDefinition
        Control0..1
        TypeReference(ValueSet)
        Is Modifierfalse
        Must Supporttrue
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        67. ObservationDefinition.normalCodedValueSet
        Definition

        The set of normal coded results for the observation.

        ShortValue set of normal coded values for the observations conforming to this ObservationDefinition
        Control0..0
        TypeReference(ValueSet)
        Is Modifierfalse
        Must Supportfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        69. ObservationDefinition.abnormalCodedValueSet
        Definition

        The set of abnormal coded results for the observation.

        ShortValue set of abnormal coded values for the observations conforming to this ObservationDefinition
        Control0..0
        TypeReference(ValueSet)
        Is Modifierfalse
        Must Supportfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        71. ObservationDefinition.criticalCodedValueSet
        Definition

        The set of critical coded results for the observation.

        ShortValue set of critical coded values for the observations conforming to this ObservationDefinition
        Control0..0
        TypeReference(ValueSet)
        Is Modifierfalse
        Must Supportfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))