Profile of EvidenceVariable for Evidence Based Medicine IG. The GroupAssignment Profile is used to classify an EvidenceVariable as an exposure managed as a categorical variable. The variable definitions are found in the category element instead of the definition element.

See Understanding the EvidenceVariable Resource for additional information.

• Key Elements Table
• Differential Table
• Snapshot Table
• Statistics/References
• All

Name	Flags	Card.	Type	Description & Constraints    Filter: Bindings Constraints Obligations
EvidenceVariable	C	0..*	VariableDefinition	A definition of an exposure, outcome, or other variable Interfaces Implemented: MetadataResource Constraints: cnl-0
EvidenceVariable.implicitRules	?! This element is a modifier element. Σ This element is included in summaries.	0..1	uri	A set of rules under which this content was created
EvidenceVariable.contained		0..*	Resource	Contained, inline Resources
EvidenceVariable.Slices for extension				Content/Rules for all slices
EvidenceVariable.Slices for extension.extension:publicationStatus		0..1	CodeableConcept	Publication status URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/artifact-publication-status Binding: Cited Artifact Status Type (preferred)
EvidenceVariable.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored Slice: Unordered, Open by value:url
EvidenceVariable.status	?! This element is a modifier element. Σ This element is included in summaries.	0..1	code	draft | active | retired | unknown Binding: PublicationStatus (required): The lifecycle status of an artifact.
EvidenceVariable.handling		1..1	CodeableConcept	boolean | continuous | dichotomous | ordinal | polychotomous | time-to-event | not-specified Binding: Evidence Variable Handling (extensible)
EvidenceVariable.category		2..*	BackboneElement	A grouping for dichotomous, ordinal, or polychotomouos variables
EvidenceVariable.category.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.category.name		1..1	string	Description of the grouping
Documentation for this format

Terminology Bindings

Path	Status	Usage	ValueSet	Version	Source
EvidenceVariable.status	Base	required	PublicationStatus	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.handling	Base	extensible	Evidence Variable Handling	📦2.0.0	THO v7.5

Constraints

Id	Grade	Path(s)	Description	Expression
cnl-0	warning	EvidenceVariable	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}$')
ele-1	error	**ALL** elements	All FHIR elements must have a @value or children	hasValue() or (children().count() > id.count())

This structure is derived from VariableDefinition

Name	Flags	Card.	Type	Description & Constraints    Filter: Bindings Constraints Obligations
EvidenceVariable		0..*	VariableDefinition	A definition of an exposure, outcome, or other variable Interfaces Implemented: MetadataResource
EvidenceVariable.definition
EvidenceVariable.definition.concept
EvidenceVariable.definition.concept.coding		1..1	Coding	Code defined by a terminology system Required Pattern: { "system" : "https://fevir.net/resources/CodeSystem/179423", "code" : "defined-in-handling-and-category", "display" : "Defined in handling and category elements" }
EvidenceVariable.category		2..*	BackboneElement	A grouping for dichotomous, ordinal, or polychotomouos variables
EvidenceVariable.category.name		1..1	string	Description of the grouping
Documentation for this format

Name	Flags	Card.	Type	Description & Constraints    Filter: Bindings Constraints Obligations
EvidenceVariable	C	0..*	VariableDefinition	A definition of an exposure, outcome, or other variable Interfaces Implemented: MetadataResource Constraints: cnl-0
EvidenceVariable.id	Σ This element is included in summaries.	0..1	id	Logical id of this artifact
EvidenceVariable.meta	Σ This element is included in summaries.	0..1	Meta	Metadata about the resource
EvidenceVariable.implicitRules	?! This element is a modifier element. Σ This element is included in summaries.	0..1	uri	A set of rules under which this content was created
EvidenceVariable.language		0..1	code	Language of the resource content Binding: AllLanguages (required): IETF language tag for a human language Additional Bindings Purpose CommonLanguages Starter
EvidenceVariable.text		0..1	Narrative	Text summary of the resource, for human interpretation This profile does not constrain the narrative in regard to content, language, or traceability to data elements
EvidenceVariable.contained		0..*	Resource	Contained, inline Resources
EvidenceVariable.Slices for extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.Slices for extension.extension:publicationStatus		0..1	CodeableConcept	Publication status URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/artifact-publication-status Binding: Cited Artifact Status Type (preferred)
EvidenceVariable.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored Slice: Unordered, Open by value:url
EvidenceVariable.url	Σ This element is included in summaries. C	0..1	uri	Canonical identifier for this evidence variable, represented as a URI (globally unique) Constraints: cnl-1
EvidenceVariable.identifier	Σ This element is included in summaries.	0..*	Identifier	Additional identifier for the evidence variable
EvidenceVariable.version	Σ This element is included in summaries.	0..1	string	Business version of the evidence variable
EvidenceVariable.versionAlgorithm[x]	Σ This element is included in summaries.	0..1		How to compare versions Binding: VersionAlgorithm (extensible)
EvidenceVariable.versionAlgorithm[x].versionAlgorithmString			string
EvidenceVariable.versionAlgorithm[x].versionAlgorithmCoding			Coding
EvidenceVariable.name	Σ This element is included in summaries. C	0..1	string	Name for this evidence variable (computer friendly)
EvidenceVariable.title	Σ This element is included in summaries.	0..1	string	Name for this evidence variable (human friendly)
EvidenceVariable.shortTitle	Σ This element is included in summaries.	0..1	string	Title for use in informal contexts
EvidenceVariable.citeAs		0..1	markdown	Display of how to cite this EvidenceVariable
EvidenceVariable.status	?! This element is a modifier element. Σ This element is included in summaries.	0..1	code	draft | active | retired | unknown Binding: PublicationStatus (required): The lifecycle status of an artifact.
EvidenceVariable.experimental		0..1	boolean	For testing only - never for real usage
EvidenceVariable.date	Σ This element is included in summaries.	0..1	dateTime	Date last changed
EvidenceVariable.author		0..*	ContactDetail	Who authored the content
EvidenceVariable.publisher	Σ This element is included in summaries.	0..1	string	Name of the publisher/steward (organization or individual)
EvidenceVariable.contact	Σ This element is included in summaries.	0..*	ContactDetail	Contact details for the publisher
EvidenceVariable.recorder		0..*	ContactDetail	Who entered the data for the evidence variable
EvidenceVariable.editor		0..*	ContactDetail	Who edited the content
EvidenceVariable.reviewer		0..*	ContactDetail	Who reviewed the content
EvidenceVariable.endorser		0..*	ContactDetail	Who endorsed the content
EvidenceVariable.description	Σ This element is included in summaries.	0..1	markdown	Natural language description of the evidence variable
EvidenceVariable.note		0..*	Annotation	Used for footnotes or explanatory notes
EvidenceVariable.useContext	Σ This element is included in summaries.	0..*	UsageContext	The context that the content is intended to support
EvidenceVariable.purpose		0..1	markdown	Why this EvidenceVariable is defined
EvidenceVariable.copyright		0..1	markdown	Intellectual property ownership, may include restrictions on use
EvidenceVariable.copyrightLabel		0..1	string	Copyright holder and year(s)
EvidenceVariable.approvalDate		0..1	date	When the resource was approved by publisher
EvidenceVariable.lastReviewDate		0..1	date	When the resource was last reviewed by the publisher
EvidenceVariable.effectivePeriod		0..1	Period	When the resource is expected to be used
EvidenceVariable.relatesTo		0..*	BackboneElement	Relationships to other Resources
EvidenceVariable.relatesTo.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.relatesTo.Slices for extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.relatesTo.Slices for extension.extension:quotation		0..1	markdown	Quoted portion from related artifact URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/relates-to-with-quotation
EvidenceVariable.relatesTo.Slices for extension.extension:classifier		0..1	CodeableConcept	A classifier of the target artifact in a relatesTo element URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/relatesto-classifier
EvidenceVariable.relatesTo.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.relatesTo.type		1..1	CodeableConcept	documentation | justification | citation | predecessor | successor | derived-from | depends-on | composed-of | part-of | amends | amended-with | appends | appended-with | cites | cited-by | comments-on | comment-in | contains | contained-in | corrects | correction-in | replaces | replaced-with | retracts | retracted-by | signs | similar-to | supports | supported-with | transforms | transformed-into | transformed-with | documents | specification-of | created-with | cite-as | reprint | reprint-of | summarizes Binding: Artifact Relationship Type (extensible): The type of relationship to the related artifact.
EvidenceVariable.relatesTo.target[x]		1..1		The artifact that is related to this EvidenceVariable
EvidenceVariable.relatesTo.target[x].targetUri			uri
EvidenceVariable.relatesTo.target[x].targetAttachment			Attachment
EvidenceVariable.relatesTo.target[x].targetCanonical			canonical(Resource)
EvidenceVariable.relatesTo.target[x].targetReference			Reference(Resource)
EvidenceVariable.relatesTo.target[x].targetMarkdown			markdown
EvidenceVariable.actual		0..1	boolean	Actual or conceptual
EvidenceVariable.definition	Σ This element is included in summaries.	0..1	CodeableReference(Group)	The meaning of the evidence variable Binding: EvidenceVariableDefinition (example)
EvidenceVariable.definition.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.definition.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.definition.concept	Σ This element is included in summaries.	0..1	CodeableConcept	Reference to a concept (by class)
EvidenceVariable.definition.concept.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.definition.concept.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.definition.concept.coding	Σ This element is included in summaries.	1..1	Coding	Code defined by a terminology system Required Pattern: { "system" : "https://fevir.net/resources/CodeSystem/179423", "code" : "defined-in-handling-and-category", "display" : "Defined in handling and category elements" }
EvidenceVariable.definition.concept.text	Σ This element is included in summaries.	0..1	string	Plain text representation of the concept
EvidenceVariable.definition.reference	Σ This element is included in summaries.	0..1	Reference()	Reference to a resource (by instance)
EvidenceVariable.definitionModifier		0..*	BackboneElement	Further specification of the definition
EvidenceVariable.definitionModifier.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.definitionModifier.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.definitionModifier.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.definitionModifier.code		1..1	CodeableConcept	Attribute of the definition Binding: EvidenceVariableDefinitionModifierCode (example)
EvidenceVariable.definitionModifier.value[x]		1..1		Specification of the definition attribute
EvidenceVariable.definitionModifier.value[x].valueCodeableConcept			CodeableConcept
EvidenceVariable.definitionModifier.value[x].valueBoolean			boolean
EvidenceVariable.definitionModifier.value[x].valueQuantity			Quantity
EvidenceVariable.definitionModifier.value[x].valueRange			Range
EvidenceVariable.definitionModifier.value[x].valuePeriod			Period
EvidenceVariable.definitionModifier.value[x].valueRelativeTime			RelativeTime
EvidenceVariable.definitionModifier.value[x].valueReference			Reference(Resource)
EvidenceVariable.definitionModifier.value[x].valueExpression			Expression
EvidenceVariable.definitionModifier.value[x].valueUri			uri
EvidenceVariable.handling		1..1	CodeableConcept	boolean | continuous | dichotomous | ordinal | polychotomous | time-to-event | not-specified Binding: Evidence Variable Handling (extensible)
EvidenceVariable.category		2..*	BackboneElement	A grouping for dichotomous, ordinal, or polychotomouos variables
EvidenceVariable.category.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.category.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.category.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.category.name		1..1	string	Description of the grouping
EvidenceVariable.category.value[x]		0..1		Definition of the grouping
EvidenceVariable.category.value[x].valueCodeableConcept			CodeableConcept
EvidenceVariable.category.value[x].valueQuantity			Quantity
EvidenceVariable.category.value[x].valueRange			Range
EvidenceVariable.category.value[x].valueReference			Reference(Group)
EvidenceVariable.conditional		0..1	Expression	Condition determining whether the data will be collected
EvidenceVariable.classifier		0..*	CodeableConcept	Classification Binding: EvidenceVariableClassifierExample (example)
EvidenceVariable.dataStorage		0..*	BackboneElement	How the data element (value of the variable) is found
EvidenceVariable.dataStorage.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.dataStorage.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.dataStorage.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.dataStorage.datatype		0..1	CodeableConcept	Type of data used to express value of the variable Binding: FHIRTypes (preferred): Either a resource or a data type, including logical model types.
EvidenceVariable.dataStorage.path		0..1	string	Where to find the data element in the dataset
EvidenceVariable.dataStorage.delimiter		0..1	string	Character(s) separating values in a string-based list
EvidenceVariable.dataStorage.component		0..*	See dataStorage (EvidenceVariable)
EvidenceVariable.timing		0..1	RelativeTime	When the variable is observed
EvidenceVariable.period		0..1	Period	Calendar-based timing when the variable is observed
EvidenceVariable.constraint		0..*	BackboneElement	Limit on acceptability of data value
EvidenceVariable.constraint.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.constraint.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.constraint.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.constraint.conditional		0..1	CodeableConcept	Condition determining whether this constraint applies Binding: AdministrativeGender (example)
EvidenceVariable.constraint.minimumQuantity		0..1	Quantity	The lowest permissible value of the variable
EvidenceVariable.constraint.maximumQuantity		0..1	Quantity	The highest permissible value of the variable
EvidenceVariable.constraint.earliestDateTime		0..1	dateTime	The earliest permissible value of the variable
EvidenceVariable.constraint.latestDateTime		0..1	dateTime	The latest permissible value of the variable
EvidenceVariable.constraint.minimumStringLength		0..1	unsignedInt	The lowest number of characters allowed for a value of the variable
EvidenceVariable.constraint.maximumStringLength		0..1	positiveInt	The highest number of characters allowed for a value of the variable
EvidenceVariable.constraint.code		0..1	CodeableConcept	Rule for acceptable data values Binding: Evidence Variable Constraint (example)
EvidenceVariable.constraint.expression		0..1	Expression	Rule for acceptable data values, as an Expression
EvidenceVariable.constraint.expectedValueSet		0..1	Reference(ValueSet)	List of anticipated values used to express value of the variable
EvidenceVariable.constraint.expectedUnitsValueSet		0..1	Reference(ValueSet)	List of anticipated values used to express units for the value of the variable
EvidenceVariable.constraint.anyValueAllowed		0..1	boolean	Permissibility of unanticipated value used to express value of the variable
EvidenceVariable.missingDataMeaning		0..*	CodeableConcept	How missing data can be interpreted Binding: DataAbsentReason (example)
EvidenceVariable.unacceptableDataHandling		0..*	CodeableConcept	How erroneous data is processed Binding: Evidence Variable Unacceptable Data Handling (example)
Documentation for this format

Terminology Bindings

Path	Status	Usage	ValueSet	Version	Source
EvidenceVariable.language	Base	required	All Languages	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.versionAlgorithm[x]	Base	extensible	Version Algorithm	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.status	Base	required	PublicationStatus	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.relatesTo.​type	Base	extensible	Artifact Relationship Type	📦1.0.0	THO v7.5
EvidenceVariable.definition	Base	example	Evidence Variable Definition	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.definitionModifier.​code	Base	example	Evidence Variable Definition Modifier Code	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.handling	Base	extensible	Evidence Variable Handling	📦2.0.0	THO v7.5
EvidenceVariable.classifier	Base	example	Evidence Variable Classifier Example	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.dataStorage.​datatype	Base	preferred	All FHIR Types	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.constraint.​conditional	Base	example	AdministrativeGender	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.constraint.​code	Base	example	Evidence Variable Constraint	📦1.0.0	THO v7.5
EvidenceVariable.missingDataMeaning	Base	example	Data Absent Reason	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.unacceptableDataHandling	Base	example	Evidence Variable Unacceptable Data Handling	📦1.0.0	THO v7.5

Constraints

Id	Grade	Path(s)	Description	Expression
cnl-0	warning	EvidenceVariable	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}$')
cnl-1	warning	EvidenceVariable.url	URL should not contain | or # - these characters make processing canonical references problematic	exists() implies matches('^[^|# ]+$')
ele-1	error	**ALL** elements	All FHIR elements must have a @value or children	hasValue() or (children().count() > id.count())

Key Elements View

Name	Flags	Card.	Type	Description & Constraints    Filter: Bindings Constraints Obligations
EvidenceVariable	C	0..*	VariableDefinition	A definition of an exposure, outcome, or other variable Interfaces Implemented: MetadataResource Constraints: cnl-0
EvidenceVariable.implicitRules	?! This element is a modifier element. Σ This element is included in summaries.	0..1	uri	A set of rules under which this content was created
EvidenceVariable.contained		0..*	Resource	Contained, inline Resources
EvidenceVariable.Slices for extension				Content/Rules for all slices
EvidenceVariable.Slices for extension.extension:publicationStatus		0..1	CodeableConcept	Publication status URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/artifact-publication-status Binding: Cited Artifact Status Type (preferred)
EvidenceVariable.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored Slice: Unordered, Open by value:url
EvidenceVariable.status	?! This element is a modifier element. Σ This element is included in summaries.	0..1	code	draft | active | retired | unknown Binding: PublicationStatus (required): The lifecycle status of an artifact.
EvidenceVariable.handling		1..1	CodeableConcept	boolean | continuous | dichotomous | ordinal | polychotomous | time-to-event | not-specified Binding: Evidence Variable Handling (extensible)
EvidenceVariable.category		2..*	BackboneElement	A grouping for dichotomous, ordinal, or polychotomouos variables
EvidenceVariable.category.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.category.name		1..1	string	Description of the grouping
Documentation for this format

Terminology Bindings

Path	Status	Usage	ValueSet	Version	Source
EvidenceVariable.status	Base	required	PublicationStatus	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.handling	Base	extensible	Evidence Variable Handling	📦2.0.0	THO v7.5

Constraints

Id	Grade	Path(s)	Description	Expression
cnl-0	warning	EvidenceVariable	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}$')
ele-1	error	**ALL** elements	All FHIR elements must have a @value or children	hasValue() or (children().count() > id.count())

Differential View

This structure is derived from VariableDefinition

Name	Flags	Card.	Type	Description & Constraints    Filter: Bindings Constraints Obligations
EvidenceVariable		0..*	VariableDefinition	A definition of an exposure, outcome, or other variable Interfaces Implemented: MetadataResource
EvidenceVariable.definition
EvidenceVariable.definition.concept
EvidenceVariable.definition.concept.coding		1..1	Coding	Code defined by a terminology system Required Pattern: { "system" : "https://fevir.net/resources/CodeSystem/179423", "code" : "defined-in-handling-and-category", "display" : "Defined in handling and category elements" }
EvidenceVariable.category		2..*	BackboneElement	A grouping for dichotomous, ordinal, or polychotomouos variables
EvidenceVariable.category.name		1..1	string	Description of the grouping
Documentation for this format

Snapshot ViewView

Name	Flags	Card.	Type	Description & Constraints    Filter: Bindings Constraints Obligations
EvidenceVariable	C	0..*	VariableDefinition	A definition of an exposure, outcome, or other variable Interfaces Implemented: MetadataResource Constraints: cnl-0
EvidenceVariable.id	Σ This element is included in summaries.	0..1	id	Logical id of this artifact
EvidenceVariable.meta	Σ This element is included in summaries.	0..1	Meta	Metadata about the resource
EvidenceVariable.implicitRules	?! This element is a modifier element. Σ This element is included in summaries.	0..1	uri	A set of rules under which this content was created
EvidenceVariable.language		0..1	code	Language of the resource content Binding: AllLanguages (required): IETF language tag for a human language Additional Bindings Purpose CommonLanguages Starter
EvidenceVariable.text		0..1	Narrative	Text summary of the resource, for human interpretation This profile does not constrain the narrative in regard to content, language, or traceability to data elements
EvidenceVariable.contained		0..*	Resource	Contained, inline Resources
EvidenceVariable.Slices for extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.Slices for extension.extension:publicationStatus		0..1	CodeableConcept	Publication status URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/artifact-publication-status Binding: Cited Artifact Status Type (preferred)
EvidenceVariable.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored Slice: Unordered, Open by value:url
EvidenceVariable.url	Σ This element is included in summaries. C	0..1	uri	Canonical identifier for this evidence variable, represented as a URI (globally unique) Constraints: cnl-1
EvidenceVariable.identifier	Σ This element is included in summaries.	0..*	Identifier	Additional identifier for the evidence variable
EvidenceVariable.version	Σ This element is included in summaries.	0..1	string	Business version of the evidence variable
EvidenceVariable.versionAlgorithm[x]	Σ This element is included in summaries.	0..1		How to compare versions Binding: VersionAlgorithm (extensible)
EvidenceVariable.versionAlgorithm[x].versionAlgorithmString			string
EvidenceVariable.versionAlgorithm[x].versionAlgorithmCoding			Coding
EvidenceVariable.name	Σ This element is included in summaries. C	0..1	string	Name for this evidence variable (computer friendly)
EvidenceVariable.title	Σ This element is included in summaries.	0..1	string	Name for this evidence variable (human friendly)
EvidenceVariable.shortTitle	Σ This element is included in summaries.	0..1	string	Title for use in informal contexts
EvidenceVariable.citeAs		0..1	markdown	Display of how to cite this EvidenceVariable
EvidenceVariable.status	?! This element is a modifier element. Σ This element is included in summaries.	0..1	code	draft | active | retired | unknown Binding: PublicationStatus (required): The lifecycle status of an artifact.
EvidenceVariable.experimental		0..1	boolean	For testing only - never for real usage
EvidenceVariable.date	Σ This element is included in summaries.	0..1	dateTime	Date last changed
EvidenceVariable.author		0..*	ContactDetail	Who authored the content
EvidenceVariable.publisher	Σ This element is included in summaries.	0..1	string	Name of the publisher/steward (organization or individual)
EvidenceVariable.contact	Σ This element is included in summaries.	0..*	ContactDetail	Contact details for the publisher
EvidenceVariable.recorder		0..*	ContactDetail	Who entered the data for the evidence variable
EvidenceVariable.editor		0..*	ContactDetail	Who edited the content
EvidenceVariable.reviewer		0..*	ContactDetail	Who reviewed the content
EvidenceVariable.endorser		0..*	ContactDetail	Who endorsed the content
EvidenceVariable.description	Σ This element is included in summaries.	0..1	markdown	Natural language description of the evidence variable
EvidenceVariable.note		0..*	Annotation	Used for footnotes or explanatory notes
EvidenceVariable.useContext	Σ This element is included in summaries.	0..*	UsageContext	The context that the content is intended to support
EvidenceVariable.purpose		0..1	markdown	Why this EvidenceVariable is defined
EvidenceVariable.copyright		0..1	markdown	Intellectual property ownership, may include restrictions on use
EvidenceVariable.copyrightLabel		0..1	string	Copyright holder and year(s)
EvidenceVariable.approvalDate		0..1	date	When the resource was approved by publisher
EvidenceVariable.lastReviewDate		0..1	date	When the resource was last reviewed by the publisher
EvidenceVariable.effectivePeriod		0..1	Period	When the resource is expected to be used
EvidenceVariable.relatesTo		0..*	BackboneElement	Relationships to other Resources
EvidenceVariable.relatesTo.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.relatesTo.Slices for extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.relatesTo.Slices for extension.extension:quotation		0..1	markdown	Quoted portion from related artifact URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/relates-to-with-quotation
EvidenceVariable.relatesTo.Slices for extension.extension:classifier		0..1	CodeableConcept	A classifier of the target artifact in a relatesTo element URL: http://hl7.org/fhir/uv/ebm/StructureDefinition/relatesto-classifier
EvidenceVariable.relatesTo.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.relatesTo.type		1..1	CodeableConcept	documentation | justification | citation | predecessor | successor | derived-from | depends-on | composed-of | part-of | amends | amended-with | appends | appended-with | cites | cited-by | comments-on | comment-in | contains | contained-in | corrects | correction-in | replaces | replaced-with | retracts | retracted-by | signs | similar-to | supports | supported-with | transforms | transformed-into | transformed-with | documents | specification-of | created-with | cite-as | reprint | reprint-of | summarizes Binding: Artifact Relationship Type (extensible): The type of relationship to the related artifact.
EvidenceVariable.relatesTo.target[x]		1..1		The artifact that is related to this EvidenceVariable
EvidenceVariable.relatesTo.target[x].targetUri			uri
EvidenceVariable.relatesTo.target[x].targetAttachment			Attachment
EvidenceVariable.relatesTo.target[x].targetCanonical			canonical(Resource)
EvidenceVariable.relatesTo.target[x].targetReference			Reference(Resource)
EvidenceVariable.relatesTo.target[x].targetMarkdown			markdown
EvidenceVariable.actual		0..1	boolean	Actual or conceptual
EvidenceVariable.definition	Σ This element is included in summaries.	0..1	CodeableReference(Group)	The meaning of the evidence variable Binding: EvidenceVariableDefinition (example)
EvidenceVariable.definition.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.definition.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.definition.concept	Σ This element is included in summaries.	0..1	CodeableConcept	Reference to a concept (by class)
EvidenceVariable.definition.concept.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.definition.concept.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.definition.concept.coding	Σ This element is included in summaries.	1..1	Coding	Code defined by a terminology system Required Pattern: { "system" : "https://fevir.net/resources/CodeSystem/179423", "code" : "defined-in-handling-and-category", "display" : "Defined in handling and category elements" }
EvidenceVariable.definition.concept.text	Σ This element is included in summaries.	0..1	string	Plain text representation of the concept
EvidenceVariable.definition.reference	Σ This element is included in summaries.	0..1	Reference()	Reference to a resource (by instance)
EvidenceVariable.definitionModifier		0..*	BackboneElement	Further specification of the definition
EvidenceVariable.definitionModifier.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.definitionModifier.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.definitionModifier.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.definitionModifier.code		1..1	CodeableConcept	Attribute of the definition Binding: EvidenceVariableDefinitionModifierCode (example)
EvidenceVariable.definitionModifier.value[x]		1..1		Specification of the definition attribute
EvidenceVariable.definitionModifier.value[x].valueCodeableConcept			CodeableConcept
EvidenceVariable.definitionModifier.value[x].valueBoolean			boolean
EvidenceVariable.definitionModifier.value[x].valueQuantity			Quantity
EvidenceVariable.definitionModifier.value[x].valueRange			Range
EvidenceVariable.definitionModifier.value[x].valuePeriod			Period
EvidenceVariable.definitionModifier.value[x].valueRelativeTime			RelativeTime
EvidenceVariable.definitionModifier.value[x].valueReference			Reference(Resource)
EvidenceVariable.definitionModifier.value[x].valueExpression			Expression
EvidenceVariable.definitionModifier.value[x].valueUri			uri
EvidenceVariable.handling		1..1	CodeableConcept	boolean | continuous | dichotomous | ordinal | polychotomous | time-to-event | not-specified Binding: Evidence Variable Handling (extensible)
EvidenceVariable.category		2..*	BackboneElement	A grouping for dichotomous, ordinal, or polychotomouos variables
EvidenceVariable.category.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.category.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.category.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.category.name		1..1	string	Description of the grouping
EvidenceVariable.category.value[x]		0..1		Definition of the grouping
EvidenceVariable.category.value[x].valueCodeableConcept			CodeableConcept
EvidenceVariable.category.value[x].valueQuantity			Quantity
EvidenceVariable.category.value[x].valueRange			Range
EvidenceVariable.category.value[x].valueReference			Reference(Group)
EvidenceVariable.conditional		0..1	Expression	Condition determining whether the data will be collected
EvidenceVariable.classifier		0..*	CodeableConcept	Classification Binding: EvidenceVariableClassifierExample (example)
EvidenceVariable.dataStorage		0..*	BackboneElement	How the data element (value of the variable) is found
EvidenceVariable.dataStorage.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.dataStorage.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.dataStorage.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.dataStorage.datatype		0..1	CodeableConcept	Type of data used to express value of the variable Binding: FHIRTypes (preferred): Either a resource or a data type, including logical model types.
EvidenceVariable.dataStorage.path		0..1	string	Where to find the data element in the dataset
EvidenceVariable.dataStorage.delimiter		0..1	string	Character(s) separating values in a string-based list
EvidenceVariable.dataStorage.component		0..*	See dataStorage (EvidenceVariable)
EvidenceVariable.timing		0..1	RelativeTime	When the variable is observed
EvidenceVariable.period		0..1	Period	Calendar-based timing when the variable is observed
EvidenceVariable.constraint		0..*	BackboneElement	Limit on acceptability of data value
EvidenceVariable.constraint.id		0..1	string	Unique id for inter-element referencing
EvidenceVariable.constraint.extension		0..*	Extension	Additional content defined by implementations Slice: Unordered, Open by value:url
EvidenceVariable.constraint.modifierExtension	?! This element is a modifier element. Σ This element is included in summaries.	0..*	Extension	Extensions that cannot be ignored even if unrecognized Slice: Unordered, Open by value:url
EvidenceVariable.constraint.conditional		0..1	CodeableConcept	Condition determining whether this constraint applies Binding: AdministrativeGender (example)
EvidenceVariable.constraint.minimumQuantity		0..1	Quantity	The lowest permissible value of the variable
EvidenceVariable.constraint.maximumQuantity		0..1	Quantity	The highest permissible value of the variable
EvidenceVariable.constraint.earliestDateTime		0..1	dateTime	The earliest permissible value of the variable
EvidenceVariable.constraint.latestDateTime		0..1	dateTime	The latest permissible value of the variable
EvidenceVariable.constraint.minimumStringLength		0..1	unsignedInt	The lowest number of characters allowed for a value of the variable
EvidenceVariable.constraint.maximumStringLength		0..1	positiveInt	The highest number of characters allowed for a value of the variable
EvidenceVariable.constraint.code		0..1	CodeableConcept	Rule for acceptable data values Binding: Evidence Variable Constraint (example)
EvidenceVariable.constraint.expression		0..1	Expression	Rule for acceptable data values, as an Expression
EvidenceVariable.constraint.expectedValueSet		0..1	Reference(ValueSet)	List of anticipated values used to express value of the variable
EvidenceVariable.constraint.expectedUnitsValueSet		0..1	Reference(ValueSet)	List of anticipated values used to express units for the value of the variable
EvidenceVariable.constraint.anyValueAllowed		0..1	boolean	Permissibility of unanticipated value used to express value of the variable
EvidenceVariable.missingDataMeaning		0..*	CodeableConcept	How missing data can be interpreted Binding: DataAbsentReason (example)
EvidenceVariable.unacceptableDataHandling		0..*	CodeableConcept	How erroneous data is processed Binding: Evidence Variable Unacceptable Data Handling (example)
Documentation for this format

Terminology Bindings

Path	Status	Usage	ValueSet	Version	Source
EvidenceVariable.language	Base	required	All Languages	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.versionAlgorithm[x]	Base	extensible	Version Algorithm	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.status	Base	required	PublicationStatus	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.relatesTo.​type	Base	extensible	Artifact Relationship Type	📦1.0.0	THO v7.5
EvidenceVariable.definition	Base	example	Evidence Variable Definition	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.definitionModifier.​code	Base	example	Evidence Variable Definition Modifier Code	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.handling	Base	extensible	Evidence Variable Handling	📦2.0.0	THO v7.5
EvidenceVariable.classifier	Base	example	Evidence Variable Classifier Example	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.dataStorage.​datatype	Base	preferred	All FHIR Types	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.constraint.​conditional	Base	example	AdministrativeGender	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.constraint.​code	Base	example	Evidence Variable Constraint	📦1.0.0	THO v7.5
EvidenceVariable.missingDataMeaning	Base	example	Data Absent Reason	📍6.0.0-snapshot1	FHIR Std.
EvidenceVariable.unacceptableDataHandling	Base	example	Evidence Variable Unacceptable Data Handling	📦1.0.0	THO v7.5

Constraints

Id	Grade	Path(s)	Description	Expression
cnl-0	warning	EvidenceVariable	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}$')
cnl-1	warning	EvidenceVariable.url	URL should not contain | or # - these characters make processing canonical references problematic	exists() implies matches('^[^|# ]+$')
ele-1	error	**ALL** elements	All FHIR elements must have a @value or children	hasValue() or (children().count() > id.count())

This structure is derived from VariableDefinition

Summary

Mandatory: 1 element(1 nested mandatory element)

Maturity: 1

See Understanding the EvidenceVariable Resource for additional information.

An example from the QUARTET USA trial will be described here and can be viewed at GroupAssignment: Quadpill vs. Candesartan.

The concepts needed to describe the group assignment for the QUARTET USA trial include:

1. This is the actual variable that was measured for analysis.
2. This variable is handled as having one of two categorical values.
3. The two categorical values that are possible for this variable are the exposure group (Quadpill) and the comparator group (Candesartan).

To communicate this is the actual variable, the EvidenceVariable.actual element has a boolean value of true:

"actual" : true

Because the definition of this variable is literally described in the EvidenceVariable.handling and EvidenceVariable.category elements, the EvidenceVariable.definition element is completed with a specific codeable concept value:

"definition" : {
    "concept" : {
      "coding" : [
        {
          "system" : "https://fevir.net/resources/CodeSystem/179423",
          "code" : "defined-in-handling-and-category",
          "display" : "Defined in handling and category elements"
        }
      ]
    }
  }

The handling of a group assignment variable may be coded as dichotomous if there are 2 possible assignments or polychotomous if there are 3 or more possible assignments. In this example with 2 possible assignments, the EvidenceVariable.handling element looks like:

"handling": {
  "coding": [
    {
      "system": "https://fevir.net/sevco",
      "code": "STATO:0000090",
      "display": "dichotomous variable"
    }
  ]
}

In prior versions of FHIR, the EvidenceVariable.handling element used a code datatype instead of a CodeableConcept datatype so looked like:

"handling": "dichotomous"

Each possible group assignment is represented as an instance in the EvidenceVariable.category element, using EvidenceVariable.category.name for a label for the category and EvidenceVariable.category.valueReference to reference the Group Resource that defines the category. The 2 groups are shown as:

"category" : [
    {
      "name" : "Quadpill once daily",
      "valueReference" : {
        "reference" : "Group/375175",
        "type" : "Group",
        "display" : "QUARTET USA Trial Quadpill group"
      }
    },
    {
      "name" : "Candesartan 8 mg once daily",
      "valueReference" : {
        "reference" : "Group/375182",
        "type" : "Group",
        "display" : "QUARTET USA Trial Control Group"
      }
    }
  ]