Part C and Part D Data Validation

This section contains information related to the validation of the Part C and Part D reporting requirements data reported to CMS by Medicare Advantage organizations and Part D sponsors. Sponsoring organizations must participate in an annual retrospective data validation of the Part C and Part D Reporting Requirements data and select a data validation contractor to conduct the audit independently per CMS’ specifications. The data validation is retrospective because it occurs in the year subsequent to the contract year (CY). For example, the data validation for CY 2022 data was conducted in 2023. To ensure the independence of the data validation, sponsoring organizations will not use their own staff and will be responsible for acquiring external data validation resources.

CMS publishes contract-level Limited Data Set (LDS) files of Part C and Part D reporting requirements data on an annual basis on the CMS LDS webpage, following the data validation process and other CMS reviews. CMS cannot guarantee that the release of these data will meet any timeframe. To request access to these LDS files, researchers must agree to certain data privacy/security requirements and data use policies by signing a Data Use Agreement (DUA) with CMS and paying the associated data processing fees. Reporting requirements and technical specifications may change from year to year. Part C and Part D reporting requirements and technical specifications can be found on the Related Links below.