HL7 Electronic Health Record System Functional Model, Release 2.1.1
2.1.1 - Normative

HL7 Electronic Health Record System Functional Model, Release 2.1.1, published by HL7 International / Electronic Health Records. This guide is not an authorized publication; it is the continuous build for version 2.1.1 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/ehrsfm-ig/ and changes regularly. See the Directory of published versions

## Extension: requirements-dependent - Detailed Descriptions

Page standards status: Normative | Maturity Level: 1

Definitions for the requirements-dependent extension

- Key Elements Table
- Differential Table
- Snapshot Table

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

0. Extension
Definition | An Extension Optional Extension Element - found in all resources.
Short | ExtensionOptional Extensions Element
Control | 0..*
Is Modifier | false
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())
2. Extension.url
Definition | Source of the definition for the extension code - a logical name or a URL.
Short | identifies the meaning of the extension
Comments | The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control | 1..1
Type | uri
Is Modifier | false
XML Format | In the XML format, this property is represented as an attribute.
Summary | false
Fixed Value | `http://hl7.org/ehrs/uv/ehrsfmr2/StructureDefinition/requirements-dependent`
4. Extension.value[x]
Definition | Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short | Value of extension
Control | 0..1 This element is affected by the following invariants: ext-1
Type | boolean, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, string, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, Expression, CodeableReference, Signature, unsignedInt, time
[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
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 foundhere

0. Extension
2. Extension.url
Fixed Value | `http://hl7.org/ehrs/uv/ehrsfmr2/StructureDefinition/requirements-dependent`
4. Extension.value[x]
Type | boolean, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, string, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note | SeeChoice of Data Typesfor further information about how to use [x]
Primitive Value | This primitive element may be present, or absent, or replaced by an extension

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

0. Extension
Definition | An Extension
Short | Extension
Control | 0..*
Is Modifier | false
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()`)
2. Extension.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
4. Extension.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 `Extension.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
6. Extension.url
Definition | Source of the definition for the extension code - a logical name or a URL.
Short | identifies the meaning of the extension
Comments | The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Control | 1..1
Type | uri
Is Modifier | false
XML Format | In the XML format, this property is represented as an attribute.
Summary | false
Fixed Value | `http://hl7.org/ehrs/uv/ehrsfmr2/StructureDefinition/requirements-dependent`
8. Extension.value[x]
Definition | Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Short | Value of extension
Control | 0..1 This element is affected by the following invariants: ext-1
Type | boolean
[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
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)