Measure Implementation

The Centers for Medicare & Medicaid Services (CMS) determines plan ratings that indicate the quality of care and experiences of beneficiaries enrolled in Medicare Advantage Prescription Drug plans (MA-PDs) and Prescription Drug Plans (PDPs), using a scale of 1 to 5 stars (inclusive of half-star ratings, e.g., 4.5 stars) with 5 stars being the highest.

As measure steward, PQA maintains the PQA measures used in Part D and provides technical guidance on the use of measures within the quality programs.

CMS manages the Part D Star Ratings program and uses its contractor, Acumen, LLC, for the analyses of Medicare data to generate the rates for the PQA measures used in Part D. CMS evaluates updates to PQA-endorsed measure specifications and drug-code lists, and has ultimate authority on what changes to PQA measures are implemented (and when).

PQA measures used in the 2027 Part D Star Ratings (Measurement Year 2025): 

• Proportion of Days Covered – Diabetes All Class (PDC-DR) (referred to by CMS as Medication Adherence for Diabetes Medications) 
• Proportion of Days Covered: Renin Angiotensin System Antagonists (PDC-RASA) (referred to by CMS as Medication Adherence for Hypertension [RAS antagonists]) 
• Proportion of Days Covered: Statins (PDC-STA) (referred to by CMS as Medication Adherence for Cholesterol [Statins])
• Statin Use in Persons with Diabetes (SUPD)
• Concurrent Use of Opioids and Benzodiazepines (COB)
• Polypharmacy: Use of Multiple Anticholinergic Medications in Older Adults (POLY_ACH)

Beyond the Star Ratings, CMS uses the Display Page to provide further evaluation of Part D plans. The Display measures do not contribute to the plan ratings but are publicly reported and can be used to facilitate quality improvement. 

PQA measures included on the 2027 Medicare Part D Display Page (Measurement Year 2025): 

• Antipsychotic Use in Persons with Dementia (APD) 
• Concurrent Use of Opioids and Benzodiazepines (COB) 
• Use of Opioids at High Dosage in Persons Without Cancer (OHD) 
• Use of Opioids from Multiple Providers in Persons Without Cancer (OMP) 
• Polypharmacy: Use of Multiple Anticholinergic Medications in Older Adults (POLY-ACH) 
• Polypharmacy: Use of Multiple Central Nervous System-Active Medications in Older Adults (POLY-CNS)
• Initial Opioid Prescribing for Long Duration (IOP-LD) 
• Persistence to Basal Insulin (PST-INS) 
• Proportion of Days Covered: Statins (PDC-STA) with Risk Adjustment (referred to by CMS as Medication Adherence for Cholesterol [Statins] with Risk Adjustment)* 
• Proportion of Days Covered: Diabetes All Class (PDC-DR) with Risk Adjustment (referred to by CMS as Medication Adherence for Diabetes Medications with Risk Adjustment)*  
• Proportion of Days Covered: Renin Angiotensin System Antagonists (PDC-RASA) with Risk Adjustment (referred to by CMS as Medication Adherence for Hypertension [RAS Antagonists] with Risk Adjustment)*
• Completion Rate for Comprehensive Medication Review (CMR) (referred to by CMS as MTM Program Completion Rate for CMR)

*The PQA PDC measures with risk adjustment were added to the 2026 Part D Display Page (Measurement Year 2024). PQA has a frequently asked questions (FAQ) document that provides background and PQA’s risk adjustment recommendations for the adherence measures in Medicare Part D.

All PQA measures used in the Medicare Part D Star Ratings and Display Page, along with one additional PQA measure, Proportion of Days Covered: Antiretroviral Medications (PDC-ARV) (referred to by CMS as Medication Adherence for HIV/AIDS [Antiretroviral]), are reported to plans in their confidential Patient Safety Reports. Part D plans can use the Patient Safety Reports to compare their performance to overall averages and monitor their progress in improving their measure rates. 

For the 2028 Medicare Part D Star Ratings (Measurement Year 2026), CMS finalized plans for the following:

• Inclusion of PQA’s risk adjustment model for the adherence measures:
  • Proportion of Days Covered: Statins (PDC-STA) with Risk Adjustment (referred to by CMS as Medication Adherence for Cholesterol [Statins] with Risk Adjustment)*
  • Proportion of Days Covered: Diabetes All Class (PDC-DR) with Risk Adjustment (referred to by CMS as Medication Adherence for Diabetes Medications with Risk Adjustment)*
  • Proportion of Days Covered: Renin Angiotensin System Antagonists (PDC-RASA) with Risk Adjustment (referred to by CMS as Medication Adherence for Hypertension [RAS Antagonists] with Risk Adjustment)*

The process for adding measures to Medicare Part D Star Ratings involves both formal rulemaking for substantive changes and the use of subregulatory guidance for technical specifications and implementation details. PQA summarizes key highlights from proposed and final rules, as well as annual advance notices and rate announcements, relevant to PQA measures and stakeholders. 

• PQA Summary of CMS 2026 Rate Announcement 
• PQA Summary of CMS-4208-F Final Rule 

The Health Insurance Marketplace Quality Rating System (QRS) is a 5-star rating system used to rate Qualified Health Plans (QHPs) based on the quality of care they provide, member experience, and how well the plan is administered. The goals of the QRS are to provide comparable and useful information to consumers about the quality of healthcare services offered by QHPs, facilitate oversight of QHPs, and to provide actionable information for QHPs to improve quality and performance. To learn more, please visit the Health Insurance Marketplace Quality Rating System website.

PQA measures used in the 2027 Health Insurance Marketplace Quality Rating System (QRS) (Measurement Year 2026):

• Proportion of Days Covered: Diabetes All Class (PDC-DR)
• Proportion of Days Covered: Renin Angiotensin System Antagonists (PDC-RASA)
• Proportion of Days Covered: Statins (PDC-STA)

Note: CMS refers to these three PDC measures in the QRS as Proportion of Days Covered: 3 Rates (PDC)

The Medicaid and Children’s Health Insurance Program (CHIP) Core Sets of Health Care Quality measures, commonly referred to as the Adult and Child Core Sets, are sets of standardized health care quality measures that CMS and states can use to measure and improve the quality of care delivered to Medicaid and CHIP beneficiaries. States submit state-level data to CMS annually, and CMS publicly publishes data on measures reported by at least 25 states that meet data quality standards. To learn more, please visit the Medicaid Child and Adult Health Care Quality Measures website.

PQA measures used in the 2026 Medicaid Adult Core Set:

• Concurrent Use of Opioids and Benzodiazepines (COB)