Centers for Medicare & Medicaid Services Data for Acute and Post-Acute Care

Dataset Details

Data Summary

These administrative data from the Centers for Medicare and Medicaid Services (CMS) contain acute care claims and post-acute care claims and assessment data for 100% of Medicare fee-for-service beneficiaries for CY2018-2021.

These are beneficiary-level, research-identifiable files which require protection and security as per Data Use Agreement requirements with CMS to prevent access to these data by anyone outside of the study team members granted access by the Data Use Agreement.

Data files include:

  • Master Beneficiary Summary File (MBSF) – Base Segment (enrollment and sociodemographic data), Chronic Conditions and Other Chronic and Disabling Conditions (flags for specific conditions), and Cost and Utilization (summary annual data on cost and utilization of specific services)
  • Medicare Provider Analysis and Review (MedPAR) file (summary action claims for inpatient stays including acute and long-term care hospitals, inpatient rehabilitation facilities, and skilled nursing facilities
  • Home Health Agency Claims
  • Outcome and Assessment Information Set – assessment data for home health patients
  • Minimum Data Set- assessment data for skilled nursing facility residents

These data enable examination of access to post-acute care following acute hospitalization, service delivery within skilled nursing facilities and home health agencies, and outcomes of post-acute care. These rich data sources may be of value to other researchers interested in studies related to hospital, skilled nursing facility, and/or home health agency services for Medicare fee-for-service beneficiaries, including specific populations by geographic factors, sociodemographic characteristics, clinical characteristics/diagnoses, and more.

Data dictionaries, technical guidance and user manuals are available on the CCW website at

Access to these data requires the completion of a data use agreement. Contact Tracy Mroz for more information.

Unit of Analysis

Patient/Medicare Beneficiary