1. Medicare Advantage organizations are missing opportunities to use ordering provider identifiers to protect program integrity Publication: Washington, D.C. : U.S. Department of Health and Human Services, Office of Inspector General, April 2021 Subject(s): Data AnalysisFraud -- prevention & controlGovernment RegulationMedical Order Entry SystemsMedicare Part C -- economicsUnited StatesUnited States. Department of Health and Human Services