Stream: implementers
Topic: Alternative valuesets for Extensible Codeable Concept
Dave Barnet (Mar 21 2017 at 16:27):
Sorry if this has been answered, and I'm sure many people out there have implemented against this. My question is whether it's OK to use an alternative valueset for an extensible codeable concept (given the rule that if the value you want to represent is in the named valueset/system you *must* use that one). As an example, the dataAbsentReason in the Observation resource lists http://hl7.org/fhir/ValueSet/observation-valueabsentreason as its extensible system, so
<coding>
<system value="http://hl7.org/fhir/ValueSet/observation-valueabsentreason"/>
<code value="not-asked"/>
<display value="Not Asked"/>
</coding>
is valid, as its from the named value set. Would
<coding>
<system value="http://snomed.info/sct"/>
<code value="47492008"/>
<display value="Not seen"/>
</coding>
also be valid (as "Not seen" is not part of the named valueset/system, but in this example is a valid data absent reason)?
To sum up, can you use a different system to the one named for an extensible codeableConcept, or must you extend the named system?
Grahame Grieve (Mar 21 2017 at 16:39):
you pretty much can't extend the named system in usual use, so you usually use a different system
Lloyd McKenzie (Mar 21 2017 at 18:20):
If the named system has the needed codes but they were excluded from the original extensible value set, then it's legitimate to use them as additional codes for an extensible value set
Last updated: Apr 12 2022 at 19:14 UTC
