I'm defining some ValueSets for use with an application and am looking for some guidance on when to use the compose property versus the expansion property to specify the values.
For a simple ValueSet that returns all contents of a code-system, definition is simple via compose.include. However, I noticed that when I retrieve this ValueSet via the $expand operation, it returns the values in the expansion property. Why is that?
For a ValueSet that represents a subset of a code-system - e.g. a set of ICD-10 codes - it seems that using the compose.include property is the way to go, explicitly specifying the codes I want included.
When would I define a ValueSet using the expansion property? Or, is this property only intended to be populated by a server in the response to an $expand API call?