Outcome Definition - Definitions - Clinical Practice Guidelines (CPG) on EBMonFHIR v1.2.0

This page is part of the CPG-on-EBMonFHIR Implementation Guide (1.2.0).

Resource Profile: OutcomeDefinition - Detailed Descriptions

Draft as of 2022-05-15

Definitions for the outcome-definition resource profile.

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

0. EvidenceVariable
2. EvidenceVariable.meta
Control	1..?
Must Support	true
4. EvidenceVariable.meta.source
Must Support	true
6. EvidenceVariable.meta.profile
Control	1..?
Must Support	true
8. EvidenceVariable.characteristic
Invariants	evidence-variable-unique-definition: For each characteristic, one and only one type of definition must exist (`( definitionReference.exists().toInteger() + definitionCanonical.exists().toInteger() + definitionCodeableConcept.exists().toInteger() + definitionExpression.exists().toInteger() + definitionId.exists().toInteger() + definitionByTypeAndValue.exists().toInteger() + definitionByCombination.exists().toInteger() ) = 1`)
10. EvidenceVariable.characteristic.exclude
Control	1..?
12. EvidenceVariable.characteristic.definitionReference
Control	0..0
14. EvidenceVariable.characteristic.definitionCanonical
Control	0..0
16. EvidenceVariable.characteristic.definitionExpression
Control	0..0
18. EvidenceVariable.characteristic.definitionId
Control	0..0
20. EvidenceVariable.handling
Control	1..?
Must Support	true

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.
Short	A 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).
Control	0..*
Is Modifier	false
Must Support	false
Summary	false
Invariants	cnl-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.meta
Definition	The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.
Short	Metadata about the resource
Control	10..1
Type	Meta
Is Modifier	false
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. EvidenceVariable.meta.source
Definition	A uri that identifies the source system of the resource. This provides a minimal amount of Provenance information that can be used to track or differentiate the source of information in the resource. The source may identify another FHIR server, document, message, database, etc. A uri that identifies the source system of the resource. This provides a minimal amount of Provenance information that can be used to track or differentiate the source of information in the resource. The source may identify another FHIR server, document, message, database, etc.
Short	Identifies where the resource comes from
Comments	The exact use of the source (and the possible implied Provenance.entity.role and agent.role) is left to implementer discretion. Only one nominated source is allowed; for additional provenance details, a full Provenance resource should be used. The source may correspond to Provenance.entity.what[x] or Provenance.agent.who[x], though it may be a more general or abstract reference. This element can be used to indicate where the current master source of a resource that has a canonical URL if the resource is no longer hosted at the canonical URL.
Control	0..1
Type	uri
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
6. EvidenceVariable.meta.profile
Definition	A list of profiles (references to StructureDefinition resources) that this resource claims to conform to. The URL is a reference to StructureDefinition.url. A list of profiles (references to StructureDefinition resources) that this resource claims to conform to. The URL is a reference to StructureDefinition.url.
Short	Profiles this resource claims to conform to
Comments	It is up to the server and/or other infrastructure of policy to determine whether/how these claims are verified and/or updated over time. The list of profile URLs is a set.
Control	10..*
Type	canonical(StructureDefinition)
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. 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.
Short	A 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.
Control	0..1
Type	uri
Is Modifier	true 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 Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. 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.
Short	Contained, 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.
Control	0..* This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
Type	Resource
Is Modifier	false
Must Support	false
Summary	false
Alternate Names	inline resources, anonymous resources, contained resources
12. 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).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Must Support	false
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content
Invariants	ele-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.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.
Short	Name 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.
Control	10..1 This element is affected by the following invariants: cnl-0
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Requirements	Support human navigation and code generation.
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
16. EvidenceVariable.status
Definition	The status of this evidence variable. Enables tracking the life-cycle of the content.
Short	draft \| 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.
Control	1..1
Binding	The codes SHALL be taken from PublicationStatushttp://hl7.org/fhir/ValueSet/publication-status\|5.0.0 (required to `http://hl7.org/fhir/ValueSet/publication-status\|5.0.0`) The lifecycle status of an artifact.
Type	code
Is Modifier	true because This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
18. EvidenceVariable.characteristic
Definition	A defining factor of the EvidenceVariable. Multiple characteristics are applied with "and" semantics.
Short	A defining factor of the EvidenceVariable
Comments	Characteristics can be defined flexibly to accommodate different use cases for membership criteria, ranging from simple codes, all the way to using an expression language to express the criteria.
Control	10..*
Type	BackboneElement
Is Modifier	false
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) evv-1: In a characteristic, at most one of these six elements shall be used: definitionReference or definitionCanonical or definitionCodeableConcept or definitionId or definitionByTypeAndValue or definitionByCombination ((definitionReference.count() + definitionCanonical.count() + definitionCodeableConcept.count() + definitionId.count() + definitionByTypeAndValue.count() + definitionByCombination.count()) < 2) evidence-variable-unique-definition: For each characteristic, one and only one type of definition must exist (`( definitionReference.exists().toInteger() + definitionCanonical.exists().toInteger() + definitionCodeableConcept.exists().toInteger() + definitionExpression.exists().toInteger() + definitionId.exists().toInteger() + definitionByTypeAndValue.exists().toInteger() + definitionByCombination.exists().toInteger() ) = 1`)
20. EvidenceVariable.characteristic.modifierExtension
Definition	May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-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.characteristic.exclude
Definition	When true, this characteristic is an exclusion criterion. In other words, not matching this characteristic definition is equivalent to meeting this criterion.
Short	Whether the characteristic is an inclusion criterion or exclusion criterion
Control	10..1
Type	boolean
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Meaning if Missing	False
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
24. EvidenceVariable.characteristic.definitionReference
Definition	Defines the characteristic using a Reference.
Short	Defines the characteristic (without using type and value) by a Reference
Control	0..01 This element is affected by the following invariants: evv-1
Type	Reference(EvidenceVariable, Group, Evidence)
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
26. EvidenceVariable.characteristic.definitionCanonical
Definition	Defines the characteristic using Canonical.
Short	Defines the characteristic (without using type and value) by a Canonical
Control	0..01 This element is affected by the following invariants: evv-1
Type	canonical(EvidenceVariable, Evidence)
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
28. EvidenceVariable.characteristic.definitionExpression
Definition	Defines the characteristic using Expression.
Short	Defines the characteristic (without using type and value) by an expression
Comments	When another element provides a definition of the characteristic, the definitionExpression content SHALL match the definition (only adding technical concepts necessary for implementation) without changing the meaning.
Control	0..01
Type	Expression
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
30. EvidenceVariable.characteristic.definitionId
Definition	Defines the characteristic using id.
Short	Defines the characteristic (without using type and value) by an id
Control	0..01 This element is affected by the following invariants: evv-1
Type	id
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
32. EvidenceVariable.characteristic.definitionByCombination
Definition	Defines the characteristic as a combination of two or more characteristics.
Short	Used to specify how two or more characteristics are combined
Control	0..1 This element is affected by the following invariants: evv-1
Type	BackboneElement
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
34. EvidenceVariable.characteristic.definitionByCombination.modifierExtension
Definition	May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
36. EvidenceVariable.characteristic.definitionByCombination.code
Definition	Used to specify if two or more characteristics are combined with OR or AND.
Short	all-of \| any-of \| at-least \| at-most \| statistical \| net-effect \| dataset
Control	1..1
Binding	The codes SHALL be taken from CharacteristicCombinationhttp://hl7.org/fhir/ValueSet/characteristic-combination\|5.0.0 (required to `http://hl7.org/fhir/ValueSet/characteristic-combination\|5.0.0`)
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Requirements	If code is "at-least" or "at-most" then threshold SHALL be used. If code is neither "at-least" nor "at-most" then threshold SHALL NOT be used.
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
38. EvidenceVariable.characteristic.definitionByCombination.characteristic
Definition	A defining factor of the characteristic.
Short	A defining factor of the characteristic
Control	1..*
Type	Seettp://hl7.org/fhir/StructureDefinition/EvidenceVariable#EvidenceVariable.characteristic
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) evidence-variable-unique-definition: For each characteristic, one and only one type of definition must exist (`( definitionReference.exists().toInteger() + definitionCanonical.exists().toInteger() + definitionCodeableConcept.exists().toInteger() + definitionExpression.exists().toInteger() + definitionId.exists().toInteger() + definitionByTypeAndValue.exists().toInteger() + definitionByCombination.exists().toInteger() ) = 1`)
40. EvidenceVariable.handling
Definition	The method of handling in statistical analysis.
Short	continuous \| dichotomous \| ordinal \| polychotomous
Control	10..1
Binding	The codes SHALL be taken from EvidenceVariableHandlinghttp://hl7.org/fhir/ValueSet/variable-handling\|5.0.0 (required to `http://hl7.org/fhir/ValueSet/variable-handling\|5.0.0`)
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	false
Invariants	ele-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.
Short	A 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).
Control	0..*
Is Modifier	false
Must Support	false
Summary	false
Invariants	cnl-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.
Short	Logical 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.
Control	0..1
Type	id
Is Modifier	false
Must Support	false
Summary	true
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.
Short	Metadata about the resource
Control	1..1
Type	Meta
Is Modifier	false
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
6. EvidenceVariable.meta.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
8. EvidenceVariable.meta.extension
Definition	May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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()`)
Slicing	This element introduces a set of slices on `EvidenceVariable.meta.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
10. EvidenceVariable.meta.versionId
Definition	The version specific identifier, as it appears in the version portion of the URL. This value changes when the resource is created, updated, or deleted.
Short	Version specific identifier
Comments	The server assigns this value, and ignores what the client specifies, except in the case that the server is imposing version integrity on updates/deletes.
Control	0..1
Type	id
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
12. EvidenceVariable.meta.lastUpdated
Definition	When the resource last changed - e.g. when the version changed.
Short	When the resource version last changed
Comments	This element is generally omitted in instances submitted in a PUT or POST. Instead, it is populated in the response instance and when retrieving information using a GET. The server / resource manager sets this value; what a client provides is irrelevant. This is equivalent to the HTTP Last-Modified and SHOULD have the same value on a read interaction.
Control	0..1
Type	instant
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
14. EvidenceVariable.meta.source
Definition	A uri that identifies the source system of the resource. This provides a minimal amount of Provenance information that can be used to track or differentiate the source of information in the resource. The source may identify another FHIR server, document, message, database, etc.
Short	Identifies where the resource comes from
Comments	The exact use of the source (and the possible implied Provenance.entity.role and agent.role) is left to implementer discretion. Only one nominated source is allowed; for additional provenance details, a full Provenance resource should be used. The source may correspond to Provenance.entity.what[x] or Provenance.agent.who[x], though it may be a more general or abstract reference. This element can be used to indicate where the current master source of a resource that has a canonical URL if the resource is no longer hosted at the canonical URL.
Control	0..1
Type	uri
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
16. EvidenceVariable.meta.profile
Definition	A list of profiles (references to StructureDefinition resources) that this resource claims to conform to. The URL is a reference to StructureDefinition.url.
Short	Profiles this resource claims to conform to
Comments	It is up to the server and/or other infrastructure of policy to determine whether/how these claims are verified and/or updated over time. The list of profile URLs is a set.
Control	1..*
Type	canonical(StructureDefinition)
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
18. EvidenceVariable.meta.security
Definition	Security labels applied to this resource. These tags connect specific resources to the overall security policy and infrastructure.
Short	Security Labels applied to this resource
Comments	The security labels can be updated without changing the stated version of the resource. The list of security labels is a set. Uniqueness is based the system/code, and version and display are ignored.
Control	0..*
Binding	Unless not suitable, these codes SHALL be taken from AllSecurityLabels (extensible to `http://hl7.org/fhir/ValueSet/security-labels`) Security Labels from the Healthcare Privacy and Security Classification System.
Type	Coding
Is Modifier	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
20. EvidenceVariable.meta.tag
Definition	Tags applied to this resource. Tags are intended to be used to identify and relate resources to process and workflow, and applications are not required to consider the tags when interpreting the meaning of a resource.
Short	Tags applied to this resource
Comments	The tags can be updated without changing the stated version of the resource. The list of tags is a set. Uniqueness is based the system/code, and version and display are ignored.
Control	0..*
Binding	For example codes, see CommonTags (example to `http://hl7.org/fhir/ValueSet/common-tags`) Codes that represent various types of tags, commonly workflow-related; e.g. "Needs review by Dr. Jones".
Type	Coding
Is Modifier	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
22. 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.
Short	A 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.
Control	0..1
Type	uri
Is Modifier	true 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 Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
24. EvidenceVariable.language
Definition	The base language in which the resource is written.
Short	Language 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).
Control	0..1
Binding	The codes SHALL be taken from AllLanguages (required to `http://hl7.org/fhir/ValueSet/all-languages\|5.0.0`) IETF language tag for a human language
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
26. 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.
Short	Text 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.
Control	0..1 This element is affected by the following invariants: dom-6
Type	Narrative
Is Modifier	false
Must Support	false
Summary	false
Alternate Names	narrative, html, xhtml, display
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
28. 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.
Short	Contained, 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.
Control	0..* This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
Type	Resource
Is Modifier	false
Must Support	false
Summary	false
Alternate Names	inline resources, anonymous resources, contained resources
30. EvidenceVariable.extension
Definition	May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Must Support	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Must Support	false
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content
Invariants	ele-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()`)
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.
Short	Canonical 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.
Control	0..1
Type	uri
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Requirements	Allows the evidence variable to be referenced by a single globally unique identifier.
Invariants	cnl-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.
Short	Additional 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.
Note	This is a business identifier, not a resource identifier (see discussion)
Control	0..*
Type	Identifier
Is Modifier	false
Must Support	false
Summary	true
Requirements	Allows externally provided and/or usable business identifiers to be easily associated with the module.
Invariants	ele-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.
Short	Business 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.
Note	This is a business version Id, not a resource version Id (see discussion)
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-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.
Short	How 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.
Control	0..1
Binding	Unless not suitable, these codes SHALL be taken from VersionAlgorithm (extensible to `http://hl7.org/fhir/ValueSet/version-algorithm`)
Type	Choice of: string, Coding
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-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.
Short	Name 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.
Control	1..1 This element is affected by the following invariants: cnl-0
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Requirements	Support human navigation and code generation.
Invariants	ele-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.
Short	Name for this evidence variable (human friendly)
Comments	This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-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.
Short	Title for use in informal contexts
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Requirements	Need to be able to reference the content by a short description, but still provide a longer, more formal title for the content.
Invariants	ele-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.
Short	draft \| 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.
Control	1..1
Binding	The codes SHALL be taken from PublicationStatus (required to `http://hl7.org/fhir/ValueSet/publication-status\|5.0.0`) The lifecycle status of an artifact.
Type	code
Is Modifier	true because This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	true
Invariants	ele-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.
Short	For testing purposes, not real usage
Control	0..1
Type	boolean
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Meaning if Missing	If absent, this resource is treated as though it is not experimental.
Invariants	ele-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.
Short	Date 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.
Control	0..1
Type	dateTime
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Alternate Names	Revision Date
Invariants	ele-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.
Short	Name 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.
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Requirements	Helps establish the "authority/credibility" of the evidence variable. May also allow for contact.
Invariants	ele-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.
Short	Contact 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.
Control	0..*
Type	ContactDetail
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-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.
Short	Natural 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).
Control	0..1
Type	markdown
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-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.
Short	Used for footnotes or explanatory notes
Control	0..*
Type	Annotation
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-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.
Short	The 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.
Control	0..*
Type	UsageContext
Is Modifier	false
Must Support	false
Summary	true
Requirements	Assist in searching for appropriate content.
Invariants	ele-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.
Short	Why 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.
Control	0..1
Type	markdown
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-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.
Short	Use and/or publishing restrictions
Control	0..1
Type	markdown
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-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').
Short	Copyright 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.
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Requirements	Defines the content expected to be rendered in all representations of the artifact.
Invariants	ele-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.
Short	When the resource was approved by publisher
Control	0..1
Type	date
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-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.
Short	When 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.
Control	0..1
Type	date
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-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.
Short	When 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.
Control	0..1
Type	Period
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-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.
Short	Who authored the content
Comments	Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).
Control	0..*
Type	ContactDetail
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-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.
Short	Who edited the content
Comments	Extensions to ContactDetail include: contactReference, contactAddress, and contributionTime (see Clinical Reasoning Module).
Control	0..*
Type	ContactDetail
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-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.
Short	Who 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.
Control	0..*
Type	ContactDetail
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-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.
Short	Who 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.
Control	0..*
Type	ContactDetail
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-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.
Short	Additional documentation, citations, etc
Comments	Each related artifact is either an attachment, or a reference to another resource, but not both.
Control	0..*
Type	RelatedArtifact
Is Modifier	false
Must Support	false
Summary	false
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.
Invariants	ele-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.
Short	Actual or conceptual
Control	0..1
Type	boolean
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
88. EvidenceVariable.characteristic
Definition	A defining factor of the EvidenceVariable. Multiple characteristics are applied with "and" semantics.
Short	A defining factor of the EvidenceVariable
Comments	Characteristics can be defined flexibly to accommodate different use cases for membership criteria, ranging from simple codes, all the way to using an expression language to express the criteria.
Control	1..*
Type	BackboneElement
Is Modifier	false
Must Support	true
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) evv-1: In a characteristic, at most one of these six elements shall be used: definitionReference or definitionCanonical or definitionCodeableConcept or definitionId or definitionByTypeAndValue or definitionByCombination (`(definitionReference.count() + definitionCanonical.count() + definitionCodeableConcept.count() + definitionId.count() + definitionByTypeAndValue.count() + definitionByCombination.count()) < 2`) evidence-variable-unique-definition: For each characteristic, one and only one type of definition must exist (`( definitionReference.exists().toInteger() + definitionCanonical.exists().toInteger() + definitionCodeableConcept.exists().toInteger() + definitionExpression.exists().toInteger() + definitionId.exists().toInteger() + definitionByTypeAndValue.exists().toInteger() + definitionByCombination.exists().toInteger() ) = 1`)
90. EvidenceVariable.characteristic.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1 This element is affected by the following invariants: ele-1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
92. EvidenceVariable.characteristic.extension
Definition	May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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()`)
94. EvidenceVariable.characteristic.modifierExtension
Definition	May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-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()`)
96. EvidenceVariable.characteristic.linkId
Definition	Label used for when a characteristic refers to another characteristic.
Short	Label for internal linking
Control	0..1
Type	id
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
98. EvidenceVariable.characteristic.description
Definition	A short, natural language description of the characteristic that could be used to communicate the criteria to an end-user.
Short	Natural language description of the characteristic
Control	0..1
Type	markdown
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Requirements	Need to be able to describe characteristics in natural language so that end users can understand the criteria.
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
100. EvidenceVariable.characteristic.note
Definition	A human-readable string to clarify or explain concepts about the characteristic.
Short	Used for footnotes or explanatory notes
Control	0..*
Type	Annotation
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
102. EvidenceVariable.characteristic.exclude
Definition	When true, this characteristic is an exclusion criterion. In other words, not matching this characteristic definition is equivalent to meeting this criterion.
Short	Whether the characteristic is an inclusion criterion or exclusion criterion
Control	1..1
Type	boolean
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Meaning if Missing	False
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
104. EvidenceVariable.characteristic.definitionReference
Definition	Defines the characteristic using a Reference.
Short	Defines the characteristic (without using type and value) by a Reference
Control	0..0 This element is affected by the following invariants: evv-1
Type	Reference(EvidenceVariable, Group, Evidence)
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
106. EvidenceVariable.characteristic.definitionCanonical
Definition	Defines the characteristic using Canonical.
Short	Defines the characteristic (without using type and value) by a Canonical
Control	0..0 This element is affected by the following invariants: evv-1
Type	canonical(EvidenceVariable, Evidence)
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
108. EvidenceVariable.characteristic.definitionCodeableConcept
Definition	Defines the characteristic using CodeableConcept.
Short	Defines the characteristic (without using type and value) by a CodeableConcept
Control	0..1 This element is affected by the following invariants: evv-1
Type	CodeableConcept
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
110. EvidenceVariable.characteristic.definitionExpression
Definition	Defines the characteristic using Expression.
Short	Defines the characteristic (without using type and value) by an expression
Comments	When another element provides a definition of the characteristic, the definitionExpression content SHALL match the definition (only adding technical concepts necessary for implementation) without changing the meaning.
Control	0..0
Type	Expression
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
112. EvidenceVariable.characteristic.definitionId
Definition	Defines the characteristic using id.
Short	Defines the characteristic (without using type and value) by an id
Control	0..0 This element is affected by the following invariants: evv-1
Type	id
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
114. EvidenceVariable.characteristic.definitionByTypeAndValue
Definition	Defines the characteristic using both a type and value[x] elements.
Short	Defines the characteristic using type and value
Control	0..1 This element is affected by the following invariants: evv-1
Type	BackboneElement
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
116. EvidenceVariable.characteristic.definitionByTypeAndValue.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1 This element is affected by the following invariants: ele-1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
118. EvidenceVariable.characteristic.definitionByTypeAndValue.extension
Definition	May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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()`)
120. EvidenceVariable.characteristic.definitionByTypeAndValue.modifierExtension
Definition	May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) ext-1: Must have either extensions or value[x], not both (`extension.exists() != value.exists()`)
122. EvidenceVariable.characteristic.definitionByTypeAndValue.type
Definition	Used to express the type of characteristic.
Short	Expresses the type of characteristic
Control	1..1
Binding	For example codes, see UsageContextType (example to `http://terminology.hl7.org/ValueSet/usage-context-type`)
Type	CodeableConcept
Is Modifier	false
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
124. EvidenceVariable.characteristic.definitionByTypeAndValue.method
Definition	Method for how the characteristic value was determined.
Short	Method for how the characteristic value was determined
Control	0..*
Binding	For example codes, see DefinitionMethod (example to `http://hl7.org/fhir/ValueSet/definition-method`)
Type	CodeableConcept
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
126. EvidenceVariable.characteristic.definitionByTypeAndValue.device
Definition	Device used for determining characteristic.
Short	Device used for determining characteristic
Control	0..1
Type	Reference(Device, DeviceMetric)
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
128. EvidenceVariable.characteristic.definitionByTypeAndValue.value[x]
Definition	Defines the characteristic when paired with characteristic.type.
Short	Defines the characteristic when coupled with characteristic.type
Control	1..1
Type	Choice of: CodeableConcept, boolean, Quantity, Range, Reference, id
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	true
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
130. EvidenceVariable.characteristic.definitionByTypeAndValue.offset
Definition	Defines the reference point for comparison when valueQuantity or valueRange is not compared to zero.
Short	Reference point for valueQuantity or valueRange
Control	0..1
Binding	For example codes, see CharacteristicOffset (example to `http://hl7.org/fhir/ValueSet/characteristic-offset`)
Type	CodeableConcept
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
132. EvidenceVariable.characteristic.definitionByCombination
Definition	Defines the characteristic as a combination of two or more characteristics.
Short	Used to specify how two or more characteristics are combined
Control	0..1 This element is affected by the following invariants: evv-1
Type	BackboneElement
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
134. EvidenceVariable.characteristic.definitionByCombination.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1 This element is affected by the following invariants: ele-1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
136. EvidenceVariable.characteristic.definitionByCombination.extension
Definition	May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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()`)
138. EvidenceVariable.characteristic.definitionByCombination.modifierExtension
Definition	May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-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()`)
140. EvidenceVariable.characteristic.definitionByCombination.code
Definition	Used to specify if two or more characteristics are combined with OR or AND.
Short	all-of \| any-of \| at-least \| at-most \| statistical \| net-effect \| dataset
Control	1..1
Binding	The codes SHALL be taken from CharacteristicCombination (required to `http://hl7.org/fhir/ValueSet/characteristic-combination\|5.0.0`)
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Requirements	If code is "at-least" or "at-most" then threshold SHALL be used. If code is neither "at-least" nor "at-most" then threshold SHALL NOT be used.
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
142. EvidenceVariable.characteristic.definitionByCombination.threshold
Definition	Provides the value of "n" when "at-least" or "at-most" codes are used.
Short	Provides the value of "n" when "at-least" or "at-most" codes are used
Control	0..1
Type	positiveInt
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
144. EvidenceVariable.characteristic.definitionByCombination.characteristic
Definition	A defining factor of the characteristic.
Short	A defining factor of the characteristic
Control	1..*
Type	Seettp://hl7.org/fhir/StructureDefinition/EvidenceVariable#EvidenceVariable.characteristic
Is Modifier	false
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`) evidence-variable-unique-definition: For each characteristic, one and only one type of definition must exist (`( definitionReference.exists().toInteger() + definitionCanonical.exists().toInteger() + definitionCodeableConcept.exists().toInteger() + definitionExpression.exists().toInteger() + definitionId.exists().toInteger() + definitionByTypeAndValue.exists().toInteger() + definitionByCombination.exists().toInteger() ) = 1`)
146. EvidenceVariable.characteristic.instances[x]
Definition	Number of occurrences meeting the characteristic.
Short	Number of occurrences meeting the characteristic
Control	0..1
Type	Choice of: Quantity, Range
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
148. EvidenceVariable.characteristic.duration[x]
Definition	Length of time in which the characteristic is met.
Short	Length of time in which the characteristic is met
Control	0..1
Type	Choice of: Quantity, Range
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
150. EvidenceVariable.characteristic.timeFromEvent
Definition	Timing in which the characteristic is determined.
Short	Timing in which the characteristic is determined
Control	0..*
Type	BackboneElement
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
152. EvidenceVariable.characteristic.timeFromEvent.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Short	Unique id for inter-element referencing
Control	0..1 This element is affected by the following invariants: ele-1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
154. EvidenceVariable.characteristic.timeFromEvent.extension
Definition	May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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()`)
156. EvidenceVariable.characteristic.timeFromEvent.modifierExtension
Definition	May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-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()`)
158. EvidenceVariable.characteristic.timeFromEvent.description
Definition	Human readable description.
Short	Human readable description
Control	0..1
Type	markdown
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
160. EvidenceVariable.characteristic.timeFromEvent.note
Definition	A human-readable string to clarify or explain concepts about the timeFromEvent.
Short	Used for footnotes or explanatory notes
Control	0..*
Type	Annotation
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
162. EvidenceVariable.characteristic.timeFromEvent.event[x]
Definition	The event used as a base point (reference point) in time.
Short	The event used as a base point (reference point) in time
Control	0..1
Binding	For example codes, see EvidenceVariableEvent (example to `http://hl7.org/fhir/ValueSet/evidence-variable-event`)
Type	Choice of: CodeableConcept, Reference, dateTime, id
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
164. EvidenceVariable.characteristic.timeFromEvent.quantity
Definition	Used to express the observation at a defined amount of time before or after the event.
Short	Used to express the observation at a defined amount of time before or after the event
Control	0..1
Type	Quantity
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
166. EvidenceVariable.characteristic.timeFromEvent.range
Definition	Used to express the observation within a period before and/or after the event.
Short	Used to express the observation within a period before and/or after the event
Control	0..1
Type	Range
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
168. EvidenceVariable.handling
Definition	The method of handling in statistical analysis.
Short	continuous \| dichotomous \| ordinal \| polychotomous
Control	1..1
Binding	The codes SHALL be taken from EvidenceVariableHandling (required to `http://hl7.org/fhir/ValueSet/variable-handling\|5.0.0`)
Type	code
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	true
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
170. EvidenceVariable.category
Definition	A grouping for ordinal or polychotomous variables.
Short	A grouping for ordinal or polychotomous variables
Control	0..*
Type	BackboneElement
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
172. 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.
Short	Unique id for inter-element referencing
Control	0..1 This element is affected by the following invariants: ele-1
Type	string
Is Modifier	false
XML Format	In the XML format, this property is represented as an attribute.
Summary	false
174. 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.
Short	Additional 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.
Control	0..*
Type	Extension
Is Modifier	false
Summary	false
Alternate Names	extensions, user content
Invariants	ele-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()`)
176. 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).
Short	Extensions 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.
Control	0..*
Type	Extension
Is Modifier	true because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summary	true
Requirements	Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.
Alternate Names	extensions, user content, modifiers
Invariants	ele-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()`)
178. EvidenceVariable.category.name
Definition	Description of the grouping.
Short	Description of the grouping
Control	0..1
Type	string
Is Modifier	false
Primitive Value	This primitive element may be present, or absent, or replaced by an extension
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
180. EvidenceVariable.category.value[x]
Definition	Definition of the grouping.
Short	Definition of the grouping
Control	0..1
Type	Choice of: CodeableConcept, Quantity, Range
[x] Note	SeeChoice of Data Typesfor further information about how to use [x]
Is Modifier	false
Must Support	false
Summary	false
Invariants	ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)