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Limited Data Set (LDS) Files

*** IMPORTANT NOTICE RELATED TO LDS REQUESTS***

We are pleased to announce the following updates occurring with the Quarter 1 2017 and annual 2016 data files:

  • A new LDS file with information about beneficiary characteristics and enrollment information for Medicare beneficiaries, the LDS Master Beneficiary Summary File (MBSF), is now available. The MBSF has additional variables that are not available in the Denominator file.  As a result, beginning with annual 2017 files, the Denominator file will be phased out and no longer available to researchers.  For more information on the LDS MBSF see: https://www.cms.gov/Research-Statistics-Data-and-Systems/Files-for-Order/LimitedDataSets/MBSF-LDS.html.

Limited Data Set Files (LDS) are identical to the previous Beneficiary Encrypted Files, but they have been stripped of data elements that might permit identification of beneficiaries. These files contain beneficiary level health information but exclude specified direct identifiers as outlined in the Health Insurance Portability and Accountability Act (HIPAA Privacy Rule).

The Centers for Medicare & Medicaid Services (CMS) is responsible for administering the Medicare, Medicaid and State Children's Health Insurance Programs, as well as a number of health oversight programs. CMS gathers and formats data to support the agency's operations. Information about Medicare beneficiaries, Medicare claims, Medicare providers, clinical data, and Medicaid eligibility and claims are included. These data are made available to the public, subject to privacy release approvals and the availability of computing resources.

Please follow the instructions on the DUA - Limited Data Sets page.