For CMS 55 and CMS 11, an hour is defined as follows:

Measure Population for emergency department visits where an inpatient encounter did not start within 119 minutes of the discharge from the emergency department. Use of <= 1 (hour(s)) operator means the difference between the end of the Emergency Department visit and the beginning of the Inpatient visit needs to be less than or equal 1 hour which spans from 0 to 119 minutes and 59 seconds.

We understand that this is because the QDM does not have the concept of rounding.Therefore, the time between ED discharge and inpatient encounter will be an hour until it is two hours (ie, 120 minutes).

The HQMF file does not have this level of detail, however, and specifies an hour (not 120 minutes). Are we permitted, under CMS, to interpret this duration as an hour up until the 120th minute and is the QDM the final authority on this. If you could point to the definitive guidance on this interpretation, that would be very helpful so we can crosswalk with the HQMF on which the measure is based.