Press release

CMS Releases Final 2015 Medicare Advantage Encounter Data to Researchers

The Centers for Medicare & Medicaid Services (CMS) announced today that final calendar year 2015 Medicare Advantage (MA) encounter data is now available to researchers under a data use agreement.  The data provides detailed information about the services received by beneficiaries enrolled in MA plans.  Researchers can use this information to help drive innovation to improve quality of care, lower costs, and to better understand the experience of patients in private health plans.

Last year, CMS released preliminary MA encounter data for the first time as part of the Trump Administration’s MyHealthEData initiative.  The initiative is focused on unleashing data to improve health outcomes and lower costs. Nearly twenty-two million beneficiaries are enrolled in MA plans, but until last year none of their utilization or diagnosis information was widely available for research. The MA encounter data contains a similar level of information as a fee-for-service claims data including provider identifiers, dates of service, type of service and diagnosis codes.

Today’s announcement demonstrates our continued commitment to ensuring researchers have access to this data in order to conduct important, innovative analyses that have the potential to drive transformation of the healthcare system said Administrator Seema Verma, “all while keeping that information private, safe and secure.”

CMS has made several improvements in the final version of 2015 MA encounter data files. These modifications include changes to the final action logic, making it easier for researchers to identify records to include in their analyses.  CMS improved chart review guidance by providing detailed explanations to identify specific actions taken with a chart review record. An updated user guide and information on these improvements is available at

Research access to the new MA encounter data files can be obtained by signing a CMS data use agreement that contains strict beneficiary privacy and data security requirements and submitting a request for research identifiable files to the CMS Research Data Assistance Center (ResDAC). To learn more, visit the ResDAC website here:

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