How should "Patient Age 12 Years or Older at Start of Measurement Period" apply to patients whose birthday is the first day of the measurement period? For example, consider a measurement period of calendar year 2018 (ie. 1/1/2018 - 12/31/2018). Would you include a patient whose birthday is 1/1/2006?

Our interpretation has been that you would not include this patient. This was partially based on the previously used "starts before start of" syntax. QDM-12 indicates that the "Age At" operator was developed as a shorthand for expressions like Patient Characteristic Birthdate: birth date” >= 12 year(s) starts before start of "Measurement Period". I read this as saying that the patient's 12th birthday must occur before the start of the measurement period.

I think, from a clinical intent standpoint, a patient whose birthday is 1/1 should not be included. Using the depression screening measure as an example (CMS2), we're trying to measure whether or not you do a depression screen within a year once the patient has turned 12. So a patient who turns 12 on January 1 should have until January 1 the following year to be marked as non-compliant, thus it doesn't really make sense to include them in the measurement period if you still have 1 day to get them into compliance.

I originally asked this question as QDM-166 but I guess it makes more sense as a CQL question now.