FHIRPath for US race

[Jozef Aerts]

I have a bit of trouble understanding how FHIRPath works on HAPI_FHIR for extensions like for US "Race".

I currently have in my code:

String fhirPath = "extension.where(url='http://hl7.org/fhir/us/core/StructureDefinition/us-core-race').extension.valueCoding.display";
String race = engine.evaluateToString(patientResource, fhirPath);

but that doesn't return anything.

I keep trying ... but any help is highly appreciated!
Best,
Jozef

[Jozef Aerts]

With some literature research and some trial and error, I found the solution. The FHIRPath must be:

"extension('http://hl7.org/fhir/us/core/StructureDefinition/us-core-race').extension.value.display"
so ... NOT using "where(...)"
and the second error I made was to use "valueCoding": it must be "value", as essentially it is value[x] ...
Hope this helps other people too! ...