| Extension |
| Definition | Optional Extensions Element - found in all resources |
| Control | 1..1 |
| Requirements | The ability to add extensions in a structured way is what keeps FHIR resources simple |
| RIM Mapping | N/A |
| Extension.url |
| Definition | Source of the definition for the extension code - a logical name or a URL |
| Control | 1..1 |
| Type | uri |
| 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 should be version specific. This will ideally be the URI for the Resource Profile defining the extension, with the code for the extension after a # |
| RIM Mapping | N/A |
| Extension.ref |
| Definition | Internal reference to context of the extension - a pointer to an xml:id in the same resource |
| Control | 0..1 |
| Type | idref |
| Comments | The order that extensions appear in is significant - where multiple extensions have the same ref id, they extend the target element in the order in which they appear in the extensions |
| RIM Mapping | N/A |
| Extension.mustUnderstand |
| Definition | If this element is set to true, then the containing resource element and its children are only safe to process if the reader understands this extension. |
| Control | 0..1 |
| Type | boolean |
| Must Understand | true |
| Comments | This value should be set to true if the value of the extension qualifies or negates data in other content |
| RIM Mapping | N/A |
| Extension.value[x] |
| Definition | Value of extension - may be a resource or one of a constraint set of the data types (see Extensibility in the spec for list) |
| Control | 0..1 |
| Type | * |
| RIM Mapping | N/A |
| Extension.extension |
| Definition | Nested Extensions - further extensions that are part of the extension |
| Control | 0..* |
| Type | Extension |
| RIM Mapping | N/A |
. Page versions: R5 R4B R4 R3 R2
This is an old version of FHIR retained for archive purposes. Do not use for anything else