The Measure resource currently defines an "effectivePeriod" element, but for measures, this information is typically specified with month/day values without years. In FHIR, tracker #21988 on the Quality Measure IG was resolved to represent this using an "anchor" (datetime) and a "range" to specify that the measure was initially effective as of some datetime, and the range of the measurement period is a year, based on that value.

The Measure resource should be changed to support this same approach, allowing the effective period for the measure to be specified with an anchor: Datetime, and range: Duration.