We're looking at generating some sample data using MeasureReport, and slightly surprised that MeasureReport.group.stratifier.stratum.component (!!) only supports coded values:

One of our components really should have a Reference-typed value (i.e., for a facet that tells you which Location (specific hospital ward) this stratum is being generated for).

Overall, it'd be good to make the component value types match http://build.fhir.org/group-definitions.html#Group.characteristic.value_x_ :

• CodeableConcept
• boolean
• Quantity
• Range
• Reference