Measurement Rationale Extension¶
| Canonical | ../StructureDefinition/measurement-rationale |
|---|---|
| Status | draft · 1.26.0 |
| Base | Extension (constraint) |
| Context | ObservationDefinition (element) |
| Source | FSH · JSON |
Why this measurement definition exists: the specific ambiguity or unit trap it prevents. Required on every definition, because a definition that cannot name the failure it prevents is a guess, and the failures this guards against (affine unit conversions, off-by-one ordinal scales) produce numbers that render and validate while being wrong. Carried as an extension because R4's ObservationDefinition has no narrative element; it retires into description on a move to R5.
Elements / Key elements
The working view: must-support, required, modifier and sliced elements from the effective (snapshot) definition.
| Element | Flags | Card. | Type | Description & Constraints |
|---|---|---|---|---|
| Extension | 0..* | Measurement Rationale Invariants: ele-1, ext-1 |
||
| url | 1..1 | http://hl7.org/fhirpath/System.String | identifies the meaning of the extension i Fixed: ../StructureDefinition/measurement-rationale |
|
| value[x] | 1..1 | string | The trap this definition prevents, in a sentence Invariants: ele-1 |