Evidence Based Medicine on FHIR Implementation Guide
2.0.0-ballot - ballot International flag

Evidence Based Medicine on FHIR Implementation Guide, published by HL7 International / Clinical Decision Support. This guide is not an authorized publication; it is the continuous build for version 2.0.0-ballot built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/ebm/ and changes regularly. See the Directory of published versions

Resource Profile: GroupAssignment - Detailed Descriptions

Page standards status: Draft Maturity Level: 1

Definitions for the group-assignment resource profile.

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

0. EvidenceVariable
2. EvidenceVariable.definition
4. EvidenceVariable.definition.concept
6. EvidenceVariable.definition.concept.coding
Control1..1
Pattern Value{
  "system" : "https://fevir.net/resources/CodeSystem/179423",
  "code" : "defined-in-handling-and-category",
  "display" : "Defined in handling and category elements"
}
8. EvidenceVariable.category
Control2..?
10. EvidenceVariable.category.name
Control1..?

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

0. EvidenceVariable
Definition

The EvidenceVariable resource describes an element that knowledge (Evidence) is about.

ShortA definition of an exposure, outcome, or other variable
Comments

The EvidenceVariable may be an exposure variable (intervention, condition, or state), a measured variable (outcome or observed parameter), or other variable (such as confounding factor).

Control0..*
Is Modifierfalse
Must Supportfalse
Summaryfalse
Invariantscnl-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.exists() implies name.matches('^[A-Z]([A-Za-z0-9_]){1,254}$'))
2. EvidenceVariable.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 its 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 its meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. EvidenceVariable.contained
Definition

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

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..*
This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
TypeResource
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesinline resources, anonymous resources, contained resources
6. EvidenceVariable.extension:classifier
Slice Nameclassifier
Definition

Classification of the variable.

ShortClassification
Control0..*
TypeExtension(EvidenceVariableClassifier) (Extension Type: CodeableConcept)
Is Modifierfalse
Must Supportfalse
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())
8. EvidenceVariable.extension:conditional
Slice Nameconditional
Definition

The context, situation, or parameters within which the variable is observed.

ShortWhen the variable is observed
Control0..1
TypeExtension(EvidenceVariableConditional) (Extension Type: Expression)
Is Modifierfalse
Must Supportfalse
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())
10. EvidenceVariable.extension:dataStorage
Slice NamedataStorage
Definition

How the data element is organized and where the data element (expressing the value of the variable) is found in the dataset.

ShortHow and where the data element (value of the variable) is found
Control0..*
TypeExtension(EvidenceVariableDataStorage) (Complex Extension)
Is Modifierfalse
Must Supportfalse
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. EvidenceVariable.extension:timing
Slice Nametiming
Definition

Timing in which the characteristic is determined or action is taken.

ShortTiming in which the characteristic is determined or action is taken
Control0..1
TypeExtension(CharacteristicTiming) (Complex Extension)
Is Modifierfalse
Must Supportfalse
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())
14. EvidenceVariable.extension:period
Slice Nameperiod
Definition

When the variable is observed in relation to calendar dates and times.

ShortDate(s) and time(s) when the variable is observed
Control0..1
TypeExtension(EvidenceVariablePeriod) (Extension Type: Period)
Is Modifierfalse
Must Supportfalse
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. EvidenceVariable.extension:constraint
Slice Nameconstraint
Definition

Limit on acceptability of data used to express values of the variable.

ShortLimit on acceptability of data value
Control0..*
TypeExtension(EvidenceVariableConstraint) (Complex Extension)
Is Modifierfalse
Must Supportfalse
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. EvidenceVariable.extension:missingDataMeaning
Slice NamemissingDataMeaning
Definition

A method or transformation applied for missing data.

ShortHow missing data is interpreted
Control0..1
TypeExtension(EvidenceVariableMissingData) (Extension Type: CodeableConcept)
Is Modifierfalse
Must Supportfalse
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. EvidenceVariable.extension:unacceptableDataHandling
Slice NameunacceptableDataHandling
Definition

A method or transformation applied for data that does not match required patterns.

ShortHow erroneous data is processed
Control0..*
TypeExtension(EvidenceVariableDataCleaning) (Extension Type: CodeableConcept)
Is Modifierfalse
Must Supportfalse
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. EvidenceVariable.modifierExtension
Definition

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

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

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
Must Supportfalse
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
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
24. EvidenceVariable.status
Definition

The status of this evidence variable. Enables tracking the life-cycle of the content.

Shortdraft | active | retired | unknown
Comments

Allows filtering of evidence variables that are appropriate for use versus not.

See guidance around (not) making local changes to elements here.


Allows filtering of evidence variables that are appropriate for use versus not.

See guidance around (not) making local changes to elements here.

Control1..1
BindingThe codes SHALL be taken from PublicationStatushttp://hl7.org/fhir/ValueSet/publication-status|6.0.0-ballot2
(required to http://hl7.org/fhir/ValueSet/publication-status|6.0.0-ballot2)

The lifecycle status of an artifact.

Typecode
Is Modifiertrue because This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
26. EvidenceVariable.handling
Definition

The method of handling in statistical analysis.

Shortcontinuous | dichotomous | ordinal | polychotomous
Control10..1
BindingThe codes SHALL be taken from EvidenceVariableHandlinghttp://hl7.org/fhir/ValueSet/variable-handling|6.0.0-ballot2
(required to http://hl7.org/fhir/ValueSet/variable-handling|6.0.0-ballot2)
Typecode
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()))
28. EvidenceVariable.category
Definition

A grouping for ordinal or polychotomous variables.

ShortA grouping for ordinal or polychotomous variables
Control20..*
TypeBackboneElement
Is Modifierfalse
Must Supportfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
30. EvidenceVariable.category.modifierExtension
Definition

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

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

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()))
32. EvidenceVariable.category.name
Definition

Description of the grouping.

ShortDescription of the grouping
Control10..1
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()))

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

0. EvidenceVariable
Definition

The EvidenceVariable resource describes an element that knowledge (Evidence) is about.

ShortA definition of an exposure, outcome, or other variable
Comments

The EvidenceVariable may be an exposure variable (intervention, condition, or state), a measured variable (outcome or observed parameter), or other variable (such as confounding factor).

Control0..*
Is Modifierfalse
Must Supportfalse
Summaryfalse
Invariantscnl-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.exists() implies name.matches('^[A-Z]([A-Za-z0-9_]){1,254}$'))
2. EvidenceVariable.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

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

Control0..1
Typeid
Is Modifierfalse
Must Supportfalse
Summarytrue
4. EvidenceVariable.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
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
6. EvidenceVariable.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 its 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 its meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. EvidenceVariable.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 SHALL be taken from AllLanguages
(required to http://hl7.org/fhir/ValueSet/all-languages|6.0.0-ballot2)

IETF language tag for a human language

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

Control0..1
This element is affected by the following invariants: dom-6
TypeNarrative
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesnarrative, html, xhtml, display
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. EvidenceVariable.contained
Definition

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

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..*
This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
TypeResource
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesinline resources, anonymous resources, contained resources
14. EvidenceVariable.extension
Definition

An Extension

ShortExtension
Control0..*
TypeExtension
Is Modifierfalse
Must Supportfalse
Summaryfalse
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 EvidenceVariable.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ url
  • 16. EvidenceVariable.extension:classifier
    Slice Nameclassifier
    Definition

    Classification of the variable.

    ShortClassification
    Control0..*
    TypeExtension(EvidenceVariableClassifier) (Extension Type: CodeableConcept)
    Is Modifierfalse
    Must Supportfalse
    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. EvidenceVariable.extension:conditional
    Slice Nameconditional
    Definition

    The context, situation, or parameters within which the variable is observed.

    ShortWhen the variable is observed
    Control0..1
    TypeExtension(EvidenceVariableConditional) (Extension Type: Expression)
    Is Modifierfalse
    Must Supportfalse
    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. EvidenceVariable.extension:dataStorage
    Slice NamedataStorage
    Definition

    How the data element is organized and where the data element (expressing the value of the variable) is found in the dataset.

    ShortHow and where the data element (value of the variable) is found
    Control0..*
    TypeExtension(EvidenceVariableDataStorage) (Complex Extension)
    Is Modifierfalse
    Must Supportfalse
    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. EvidenceVariable.extension:timing
    Slice Nametiming
    Definition

    Timing in which the characteristic is determined or action is taken.

    ShortTiming in which the characteristic is determined or action is taken
    Control0..1
    TypeExtension(CharacteristicTiming) (Complex Extension)
    Is Modifierfalse
    Must Supportfalse
    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())
    24. EvidenceVariable.extension:period
    Slice Nameperiod
    Definition

    When the variable is observed in relation to calendar dates and times.

    ShortDate(s) and time(s) when the variable is observed
    Control0..1
    TypeExtension(EvidenceVariablePeriod) (Extension Type: Period)
    Is Modifierfalse
    Must Supportfalse
    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())
    26. EvidenceVariable.extension:constraint
    Slice Nameconstraint
    Definition

    Limit on acceptability of data used to express values of the variable.

    ShortLimit on acceptability of data value
    Control0..*
    TypeExtension(EvidenceVariableConstraint) (Complex Extension)
    Is Modifierfalse
    Must Supportfalse
    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())
    28. EvidenceVariable.extension:missingDataMeaning
    Slice NamemissingDataMeaning
    Definition

    A method or transformation applied for missing data.

    ShortHow missing data is interpreted
    Control0..1
    TypeExtension(EvidenceVariableMissingData) (Extension Type: CodeableConcept)
    Is Modifierfalse
    Must Supportfalse
    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. EvidenceVariable.extension:unacceptableDataHandling
    Slice NameunacceptableDataHandling
    Definition

    A method or transformation applied for data that does not match required patterns.

    ShortHow erroneous data is processed
    Control0..*
    TypeExtension(EvidenceVariableDataCleaning) (Extension Type: CodeableConcept)
    Is Modifierfalse
    Must Supportfalse
    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())
    32. EvidenceVariable.modifierExtension
    Definition

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

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

    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
    Must Supportfalse
    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
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    34. EvidenceVariable.url
    Definition

    An absolute URI that is used to identify this evidence variable when it is referenced in a specification, model, design or an instance; also called its canonical identifier. This SHOULD be globally unique and SHOULD be a literal address at which an authoritative instance of this evidence variable is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the evidence variable is stored on different servers.

    ShortCanonical identifier for this evidence variable, represented as a URI (globally unique)
    Comments

    In some cases, the resource can no longer be found at the stated url, but the url itself cannot change. Implementations can use the meta.source element to indicate where the current master source of the resource can be found.

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

    Allows the evidence variable to be referenced by a single globally unique identifier.

    Invariantscnl-1: URL should not contain | or # - these characters make processing canonical references problematic (exists() implies matches('^[^|# ]+$'))
    ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    36. EvidenceVariable.identifier
    Definition

    A formal identifier that is used to identify this evidence variable when it is represented in other formats, or referenced in a specification, model, design or an instance.

    ShortAdditional identifier for the evidence variable
    Comments

    Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, and can then identify this evidence variable outside of FHIR, where it is not possible to use the logical URI.

    NoteThis is a business identifier, not a resource identifier (see discussion)
    Control0..*
    TypeIdentifier
    Is Modifierfalse
    Must Supportfalse
    Summarytrue
    Requirements

    Allows externally provided and/or usable business identifiers to be easily associated with the module.

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

    The identifier that is used to identify this version of the evidence variable when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the evidence variable author and is not expected to be globally unique. For example, it might be a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation that versions can be placed in a lexicographical sequence. To provide a version consistent with the Decision Support Service specification, use the format Major.Minor.Revision (e.g. 1.0.0). For more information on versioning knowledge assets, refer to the Decision Support Service specification. Note that a version is required for non-experimental active artifacts.

    ShortBusiness version of the evidence variable
    Comments

    There may be different evidence variable instances that have the same identifier but different versions. The version can be appended to the url in a reference to allow a reference to a particular business version of the evidence variable with the format [url]|[version]. The version SHOULD NOT contain a '#' - see Business Version.

    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
    Must Supportfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    40. EvidenceVariable.versionAlgorithm[x]
    Definition

    Indicates the mechanism used to compare versions to determine which is more current.

    ShortHow to compare versions
    Comments

    If set as a string, this is a FHIRPath expression that has two additional context variables passed in - %version1 and %version2 and will return a negative number if version1 is newer, a positive number if version2 is newer, and a 0 if the version ordering can't successfully be determined.

    Control0..1
    BindingUnless not suitable, these codes SHALL be taken from VersionAlgorithm
    (extensible to http://hl7.org/fhir/ValueSet/version-algorithm)
    TypeChoice of: string, Coding
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    42. EvidenceVariable.name
    Definition

    A natural language name identifying the evidence variable. This name should be usable as an identifier for the module by machine processing applications such as code generation.

    ShortName for this evidence variable (computer friendly)
    Comments

    The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.

    Control0..1
    This element is affected by the following invariants: cnl-0
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summarytrue
    Requirements

    Support human navigation and code generation.

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

    A short, descriptive, user-friendly title for the evidence variable.

    ShortName for this evidence variable (human friendly)
    Comments

    This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.

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

    The short title provides an alternate title for use in informal descriptive contexts where the full, formal title is not necessary.

    ShortTitle for use in informal contexts
    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summarytrue
    Requirements

    Need to be able to reference the content by a short description, but still provide a longer, more formal title for the content.

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

    The status of this evidence variable. Enables tracking the life-cycle of the content.

    Shortdraft | active | retired | unknown
    Comments

    Allows filtering of evidence variables that are appropriate for use versus not.

    See guidance around (not) making local changes to elements here.

    Control1..1
    BindingThe codes SHALL be taken from PublicationStatus
    (required to http://hl7.org/fhir/ValueSet/publication-status|6.0.0-ballot2)

    The lifecycle status of an artifact.

    Typecode
    Is Modifiertrue because This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    50. EvidenceVariable.experimental
    Definition

    A Boolean value to indicate that this resource is authored for testing purposes (or education/evaluation/marketing) and is not intended to be used for genuine usage.

    ShortFor testing purposes, not real usage
    Control0..1
    Typeboolean
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summaryfalse
    Meaning if MissingIf absent, this resource is treated as though it is not experimental.
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    52. EvidenceVariable.date
    Definition

    The date (and optionally time) when the evidence variable was last significantly changed. The date must change when the business version changes and it must change if the status code changes. In addition, it should change when the substantive content of the evidence variable changes.

    ShortDate last changed
    Comments

    The date is often not tracked until the resource is published, but may be present on draft content. Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the evidence variable. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.

    See guidance around (not) making local changes to elements here.

    Control0..1
    TypedateTime
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summarytrue
    Alternate NamesRevision Date
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    54. EvidenceVariable.publisher
    Definition

    The name of the organization or individual responsible for the release and ongoing maintenance of the evidence variable.

    ShortName of the publisher/steward (organization or individual)
    Comments

    Usually an organization but may be an individual. The publisher (or steward) of the evidence variable is the organization or individual primarily responsible for the maintenance and upkeep of the evidence variable. This is not necessarily the same individual or organization that developed and initially authored the content. The publisher is the primary point of contact for questions or issues with the evidence variable. This item SHOULD be populated unless the information is available from context.

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

    Helps establish the "authority/credibility" of the evidence variable. May also allow for contact.

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

    Contact details to assist a user in finding and communicating with the publisher.

    ShortContact details for the publisher
    Comments

    Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).

    See guidance around (not) making local changes to elements here.

    Control0..*
    TypeContactDetail
    Is Modifierfalse
    Must Supportfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    58. EvidenceVariable.description
    Definition

    A free text natural language description of the evidence variable from a consumer's perspective.

    ShortNatural language description of the evidence variable
    Comments

    This description can be used to capture details such as comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the evidence variable as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context (e.g. the language of the evidence variable is presumed to be the predominant language in the place the evidence variable was created).

    Control0..1
    Typemarkdown
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supportfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    60. EvidenceVariable.note
    Definition

    A human-readable string to clarify or explain concepts about the resource.

    ShortUsed for footnotes or explanatory notes
    Control0..*
    TypeAnnotation
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    62. EvidenceVariable.useContext
    Definition

    The content was developed with a focus and intent of supporting the contexts that are listed. These contexts may be general categories (gender, age, ...) or may be references to specific programs (insurance plans, studies, ...) and may be used to assist with indexing and searching for appropriate evidence variable instances.

    ShortThe context that the content is intended to support
    Comments

    When multiple useContexts are specified, there is no expectation that all or any of the contexts apply.

    Control0..*
    TypeUsageContext
    Is Modifierfalse
    Must Supportfalse
    Summarytrue
    Requirements

    Assist in searching for appropriate content.

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

    Explanation of why this EvidenceVariable is needed and why it has been designed as it has.

    ShortWhy this EvidenceVariable is defined
    Comments

    This element does not describe the usage of the EvidenceVariable. Instead, it provides traceability of ''why'' the resource is either needed or ''why'' it is defined as it is. This may be used to point to source materials or specifications that drove the structure of this EvidenceVariable.

    Control0..1
    Typemarkdown
    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()))
    66. EvidenceVariable.copyright
    Definition

    A copyright statement relating to the resource and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the resource.

    ShortUse and/or publishing restrictions
    Control0..1
    Typemarkdown
    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()))
    68. EvidenceVariable.copyrightLabel
    Definition

    A short string (<50 characters), suitable for inclusion in a page footer that identifies the copyright holder, effective period, and optionally whether rights are resctricted. (e.g. 'All rights reserved', 'Some rights reserved').

    ShortCopyright holder and year(s)
    Comments

    The (c) symbol should NOT be included in this string. It will be added by software when rendering the notation. Full details about licensing, restrictions, warrantees, etc. goes in the more general 'copyright' element.

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

    Defines the content expected to be rendered in all representations of the artifact.

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

    The date on which the resource content was approved by the publisher. Approval happens once when the content is officially approved for usage.

    See guidance around (not) making local changes to elements here.

    ShortWhen the resource was approved by publisher
    Control0..1
    Typedate
    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()))
    72. EvidenceVariable.lastReviewDate
    Definition

    The date on which the resource content was last reviewed. Review happens periodically after approval but does not change the original approval date.

    ShortWhen the resource was last reviewed by the publisher
    Comments

    If specified, this date follows the original approval date.

    See guidance around (not) making local changes to elements here.

    Control0..1
    Typedate
    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()))
    74. EvidenceVariable.effectivePeriod
    Definition

    The period during which the resource content was or is planned to be in active use.

    ShortWhen the resource is expected to be used
    Comments

    The effective period for an EvidenceVariable determines when the content is applicable for usage and is independent of publication and review dates. For example, a variable intended to be used for the year 2016 might be published in 2015.

    See guidance around (not) making local changes to elements here.

    Control0..1
    TypePeriod
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    76. EvidenceVariable.author
    Definition

    An individiual or organization primarily involved in the creation and maintenance of the content.

    ShortWho authored the content
    Comments

    Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).

    Control0..*
    TypeContactDetail
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    78. EvidenceVariable.editor
    Definition

    An individual or organization primarily responsible for internal coherence of the content.

    ShortWho edited the content
    Comments

    Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).

    Control0..*
    TypeContactDetail
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    80. EvidenceVariable.reviewer
    Definition

    An individual or organization asserted by the publisher to be primarily responsible for review of some aspect of the content.

    ShortWho reviewed the content
    Comments

    Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).

    See guidance around (not) making local changes to elements here.

    Control0..*
    TypeContactDetail
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    82. EvidenceVariable.endorser
    Definition

    An individual or organization asserted by the publisher to be responsible for officially endorsing the content for use in some setting.

    ShortWho endorsed the content
    Comments

    Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).

    See guidance around (not) making local changes to elements here.

    Control0..*
    TypeContactDetail
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    84. EvidenceVariable.relatedArtifact
    Definition

    Related artifacts such as additional documentation, justification, or bibliographic references.

    ShortAdditional documentation, citations, etc
    Comments

    Each related artifact is either an attachment, or a reference to another resource, but not both.

    Control0..*
    TypeRelatedArtifact
    Is Modifierfalse
    Must Supportfalse
    Summaryfalse
    Requirements

    EvidenceVariables must be able to provide enough information for consumers of the content (and/or interventions or results produced by the content) to be able to determine and understand the justification for and evidence in support of the content.

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

    True if the actual variable measured, false if a conceptual representation of the intended variable.

    ShortActual or conceptual
    Control0..1
    Typeboolean
    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()))
    88. EvidenceVariable.definition
    Definition

    Defines the variable with a concept and/or Reference.

    ShortDefines the variable with a concept and/or Reference
    Control0..1
    BindingFor example codes, see EvidenceVariableDefinition
    (example to http://hl7.org/fhir/ValueSet/evidence-variable-definition)
    TypeCodeableReference(Group)
    Is Modifierfalse
    Must Supportfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    90. EvidenceVariable.definition.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
    This element is affected by the following invariants: ele-1
    Typeid
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    92. EvidenceVariable.definition.extension
    Definition

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

    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()))
    SlicingThis element introduces a set of slices on EvidenceVariable.definition.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
    • value @ url
    • 94. EvidenceVariable.definition.concept
      Definition

      A reference to a concept - e.g. the information is identified by its general class to the degree of precision found in the terminology.

      ShortReference to a concept (by class)
      Control0..1
      TypeCodeableConcept
      Is Modifierfalse
      Summaryfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      96. EvidenceVariable.definition.concept.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
      This element is affected by the following invariants: ele-1
      Typeid
      Is Modifierfalse
      XML FormatIn the XML format, this property is represented as an attribute.
      Summaryfalse
      98. EvidenceVariable.definition.concept.extension
      Definition

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

      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()))
      SlicingThis element introduces a set of slices on EvidenceVariable.definition.concept.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
      • value @ url
      • 100. EvidenceVariable.definition.concept.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..1
        TypeCoding
        Is Modifierfalse
        Summaryfalse
        Requirements

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

        Pattern Value{
          "system" : "https://fevir.net/resources/CodeSystem/179423",
          "code" : "defined-in-handling-and-category",
          "display" : "Defined in handling and category elements"
        }
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        102. EvidenceVariable.definition.concept.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
        Summaryfalse
        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()))
        104. EvidenceVariable.definition.reference
        Definition

        A reference to a resource the provides exact details about the information being referenced.

        ShortReference to a resource (by instance)
        Control0..1
        TypeReference
        Is Modifierfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        106. EvidenceVariable.handling
        Definition

        The method of handling in statistical analysis.

        Shortcontinuous | dichotomous | ordinal | polychotomous
        Control1..1
        BindingThe codes SHALL be taken from EvidenceVariableHandling
        (required to http://hl7.org/fhir/ValueSet/variable-handling|6.0.0-ballot2)
        Typecode
        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()))
        108. EvidenceVariable.category
        Definition

        A grouping for ordinal or polychotomous variables.

        ShortA grouping for ordinal or polychotomous variables
        Control2..*
        TypeBackboneElement
        Is Modifierfalse
        Must Supportfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        110. EvidenceVariable.category.id
        Definition

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

        ShortUnique id for inter-element referencing
        Control0..1
        This element is affected by the following invariants: ele-1
        Typestring
        Is Modifierfalse
        XML FormatIn the XML format, this property is represented as an attribute.
        Summaryfalse
        112. EvidenceVariable.category.extension
        Definition

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

        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()))
        114. EvidenceVariable.category.modifierExtension
        Definition

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

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

        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()))
        116. EvidenceVariable.category.name
        Definition

        Description of the grouping.

        ShortDescription of the grouping
        Control1..1
        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()))
        118. EvidenceVariable.category.value[x]
        Definition

        Definition of the grouping.

        ShortDefinition of the grouping
        Control0..1
        TypeChoice of: CodeableConcept, Quantity, Range, Reference(Group)
        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
        Is Modifierfalse
        Must Supportfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))