Description

Medicare is a federal health insurance program for persons 65 years and older, persons with certain disabilities, and persons with end-stage renal disease. Medicare claims are payments from the Centers for Medicare & Medicaid Services (CMS) to health care providers (hospitals, outpatient clinics, physicians) for services rendered, including institutional costs covered under Medicare Parts A and B and physician services covered under Medicare Part B. The denominator files include beneficiary demographic characteristics, dates of death, and program eligibility and enrollment information. These data can be used to study disease, health care utilization, costs, and longitudinal outcomes of Medicare-eligible beneficiaries.

Key Considerations

• What kind of Medicare data is right for my study? (Comparison of RIF, LDS, and PUF)

• Annual vs. Quarterly data: Quarterly data is more recent but less mature than annual data. It incurs an additional cost when accessed through the VRDC.

  • RIF quarterly data

  • LDS quarterly data

  • FFS quarterly FAQs

• PopHealth DataShare available data assets

• What Medicare Parts A, B, C, and D covers

• Medicare Advantage rates have changed over time (18% in 1999 vs 39% in 2020). This translates to smaller proportions of Medicare fee-for-service beneficiaries available for analytic cohort analyses from our samples over time.

  • Medicare Advantage Enrollment Trends

  • Medicare Advantage National Penetration Rates

• On-site asset vs. VRDC access

• Cost

  • DataShare users may access stock assets through an annual fee.

  • Researchers who do not use DataShare's stock assets need to purchase data access from CMS. There are separate fee lists for physical data and data accessed via the VRDC.

• Sample size

  • Medicare total enrollment: Information on all Medicare enrollees by geography, type of coverage, type of entitlement, and demographic characteristics

  • Cohort size estimate tool

  • Medicare enrollment dashboard: Interactive tool that shows monthly and annual fee-for-service medical coverage, Medicare Advantage, and prescription drug coverage enrollment by geography

Governance

• Access to Medicare data requires a CMS Data Use Agreement (DUA). The DUA must also be linked to a CMS Data Management Plan Self-Attestation Questionnaire (DMP SAQ). Please contact DataShare for more information.

• SAQ overview and decision tree

• When may new CMS data be requested? When is it released?

Medicare Wiki Content

Most content is access-restricted to Medicare DataShare users. Click content to request access. 

More Information

• Analysis Resources (authorized users)

• Commonly-Linked Data Assets

• Glossary of Abbreviations

• I still have questions. Whom should I ask?