For data that is exchanged today though non FHIR methods we have seen groups exchange measures calculated with multiple ways. Primarily the difference between Rolling 12 Months and Year to Date. This is usually due to Rolling 12 giving value in knowing when the patient will require a task. While Year to Date is typically how outcomes used for reporting are calculated. If a group would like to send both for a measure today we would have to do something odd with the periods (by shifting them) or using different measure definitions for the two gaps.

Suggested Solution: Extend MeasureReport to hold a distinction between Rolling 12 calculations and Year to Date with a new coding. 

Alternate Solution: Extend Measure to hold the same distinction (but this would be less ideal as there would be more Measure resources for folks to utilize).