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Both modules of the Medicare Current Beneficiary Survey (MCBS) come standard with Medicare claims data. The claims data included with the MCBS are for beneficiaries found in the module requested and are claims for the year of the file. 
Historical/future claims for current participants or claims for past participants are not included in the standard release. Occasionally researchers need to obtain identifiable data for MCBS participants, such as the Vital Status file to get up to date death information.

Request Process

The MCBS data is considered to be a Limited Data Set (LDS). Requests for LDS data require fewer request materials and do not require a CMS Privacy Board review. If a researcher is requesting MCBS in combination with identifiable data, then the whole request becomes an identifiable (RIF) data request. The study must meet the criteria for an identifiable data request and the researcher will need to submit the documentation for identifiable data rather than a MCBS-only request. The documents required for an identifiable data request can be found on the ResDAC website.

Logistics for the Linkage

Researchers requesting to link the MCBS data to identifiable data distributed by the Chronic Condition Warehouse (CCW) contractor will need to request a “BASE ID to BENE ID crosswalk.” The BASE ID is the unique identifier in the MCBS and the BENE ID is the unique identifier in the CCW data. The MCBS cannot be linked to LDS claims data distributed by CMS.