http://hl7.org/fhir/StructureDefinition/observation-precondition|4.0.1
Other preceding or concurrent observations that must be known to correctly interpret the the observation. For example an fiO2 measure taken alongside of a SpO2 measurement. See the [Observation notes](observation.html#notes) section for additional guidance.
| type | destination |
|---|---|
| baseDefinition | http://hl7.org/fhir/StructureDefinition/Extension |
| type | http://hl7.org/fhir/StructureDefinition/Extension |
| Extension.value[x].type | http://hl7.org/fhir/StructureDefinition/Reference |
| Extension.value[x].targetProfile | http://hl7.org/fhir/StructureDefinition/Observation |