1. Medicare Part D: CMS should monitor effects of rebates on plan formularies and beneficiary spending : report to congressional requesters Publication: Washington, DC : United States Government Accountability Office, September 2023 Subject(s): Drug CostsGovernment RegulationLegislation, MedicalMedicare Part D -- economicsMedicare Part D -- organization & administrationPrescription FeesUnited StatesCenters for Medicare & Medicaid Services (U.S.)