Extension 
url 
value[x] Documentation for this formatThis is the set of resources that conform to both Observation Precondition (http://hl7.org/fhir/StructureDefinition/observation-precondition) and Observation Precondition (http://hl7.org/fhir/StructureDefinition/observation-precondition).
| Name | Flags | Card. | Type | Description & Constraints Filter: |
|---|---|---|---|---|
| Extension | 0..* | Other Observations needed to understand the context and significance of the source observation. | ||
| url | 1..1 | uri | identifies the meaning of the extension | |
| value[x] | 1..1 | Reference(Observation) | Value of extension | |
| Documentation for this format | ||||