Brief Description of Measure:
​CMS645: Bone density evaluation for patients with prostate cancer and receiving androgen deprivation therapy:
Patients determined as having prostate cancer who are currently starting or undergoing androgen deprivation therapy (ADT), for an anticipated period of 12 months or greater and who receive an initial bone density evaluation. The bone density evaluation must be prior to the start of ADT or within 3 months of the start of ADT.

Description of Issue:
A recent Jira submission raised a concern that patients whose prostate cancer diagnosis began before the measurement period and also ended before the start of the measurement period ​remain in the initial population of the measure, as currently specified. The applied timing of 'starts same day or before end' addressed the start of the prostate cancer diagnosis, but does not address the end of the prostate cancer diagnosis. Revising the timing to 'overlaps' will anchor the prostate cancer to the measurement period.

Proposed Solution:
Revise the 'Prostate Cancer Diagnosis' definition to replace the timing of "starts same day or before end" with "overlaps": 
 
Current Prostate Cancer Diagnosis:
["Diagnosis": "Prostate Cancer"] ProstateCancer
  where ProstateCancer.prevalencePeriod starts same day or before end "Measurement Period"
 
Proposed Prostate Cancer Diagnosis
["Diagnosis": "Prostate Cancer"] ProstateCancer
  where ProstateCancer.prevalencePeriod overlaps "Measurement Period" 

Rationale for Change:
Although prostate cancer is monitored for years and the diagnosis may never end, the logic should limit the inclusion of the patient to the initial population and should not allow resolved prostate cancer to count years later.