This page is part of the FHIR Specification (v4.3.0: R4B -  STU). This is a downloaded version of the specification.  For a full list of available versions, see the Directory of published versions 
FHIR Infrastructure   Work Group | Maturity Level: Normative | Standards Status: Normative | 
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   This page has been approved as part of an ANSI   standard.
   See the Infrastructure Package for further details.
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| Element | |||||||||||||
| Standards Status | This element has a standards status of "Normative" | ||||||||||||
| Definition | Base definition for all elements in a resource.  | ||||||||||||
| Cardinality | 0..* | ||||||||||||
| Invariants | 
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| Element.id | |||||||||||||
| Definition | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.  | ||||||||||||
| Cardinality | 0..1 | ||||||||||||
| Type | string | ||||||||||||
| Element.extension | |||||||||||||
| Definition | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.  | ||||||||||||
| Cardinality | 0..* | ||||||||||||
| Type | Extension | ||||||||||||
| Alternate Names | extensions; user content | ||||||||||||
| 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.  | ||||||||||||