Brief Description of Measure:

Multiple EH eCQMs

Description of Issue:

Currently, the age criteria logic used in most measures uses the 'Global.CalendarageInYearsAt' function, and restates the interval for birthDatetime. This function is being removed from the Measure Authoring Tool Global Common Library to refine the logic, ease human readability, and take advantage of capability within the CQL specification.
 
This change streamlines the logic and also removes the datatype, 'Patient Characteristic Birthdate' and associated Birth date LOINC code from the human readable version of the measure.
 
Earlier CRP feedback supported this change:CQM-4903 ​Replace age calculation function - Office of the National Coordinator for Health Information Technology (healthit.gov), however, we are re-circulating to obtain broader feedback and to highlight the removal of the Patient Characteristic Birthdate dataype from the measure logic.

Proposed Solution:

​Remove the 'Global.CalendarAgeInYearsAt' and' Global.CalendarAgeInMonthsAt' functions and replace with 'AgeInYearsAt' and 'AgeInMonthsAt' functions for all applicable CQL libraries and measures.
 

Examples of new age calculation logic can be found here:https://github.com/cqframework/CQL-Formatting-and-Usage-Wiki/blob/master/Source/Cooking%20With%20CQL/57/AgeCalculationExample.cql
Rationale for Change:

​Updating and refining the age criteria to use the native function 'AgeInYearsAt' eases human readability, and takes advantage of inherent capability within the CQL specification. The revised age function accesses the birthdate element of the patient to retrieve the value using the model info and CQL-ELM translator.