Keying review efforts to geographic variations.
D003625:Data Collection; D003955:Diagnostic Tests, Routine; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D008404:Massachusetts; D012017:Referral and Consultation; D012040:Regional Health Planning; D013514:Surgical Procedures, Operative / Q000706:statistics & numerical data; D014600:Utilization Review / Q000379:methods*