NCHS Data Linkage

NCHS Data Linked to CMS Medicare Data Files

NCHS has linked data from various surveys with Medicare program enrollment and health care utilization and expenditure data from the Centers for Medicare & Medicaid Services (CMS). Linkage of the NCHS survey participants with the CMS Medicare data provides the opportunity to study changes in health status, health care utilization and costs, and prescription drug use among Medicare enrollees. Medicare is the federal health insurance program for people who are 65 or older, certain younger people with disabilities, and people with End-Stage Renal Disease.

Linked Medicare data are available for those NCHS survey participants who consented for linkage, agreed to provide personal identification data to NCHS and for whom NCHS was able to match with Medicare administrative records. The linked Medicare data files include Medicare enrollment, Fee-for-Service health care claims and Medicare Advantage patient encounters, prescription drug event records, and clinical assessment data for patients residing in nursing homes or receiving home health care services.

NCHS has  linked the following surveys* to 2014-2018 Medicare enrollment data, fee-for-service (FFS) claims, prescription drug events, and patient assessments and to 2016-2018 Medicare Advantage encounter data:

  • 1994-2018 National Health Interview Survey (NHIS)
  • 1999-2018 Continuous National Health and Nutrition Examination Survey (NHANES)
  • Third National Health and Nutrition Examination Survey (NHANES III)
  • 2004 National Nursing Home Survey (NNHS)

* For 1994-1998 NHIS and 2004 NNHS, only 2014–2018 Medicare Beneficiary Summary File (MBSF) data; 2016-2018 FFS claims, prescription drug events, and patient assessments; and 2016 Medicare Advantage encounter data are available.

Additionally, NCHS previously linked 1999-2013* CMS Medicare enrollment, FFS claims and prescription drug events data for the following NCHS surveys:

  • 1994-2013 NHIS
  • 1999-2012 Continuous NHANES
  • 2004 NNHS

* 1991-1998 linked NCHS-CMS Medicare data are available from a previous linkage for some of the surveys listed. Please contact the NCHS Data Linkage Team for more information.

 Linked NCHS-CMS Medicare Data Bibliography


The details of the linked data, linkage methods, and analysis considerations, are available from the links on the navigation menu. For any additional questions, contact the Data Linkage Team:

Data Linkage Team
Division of Analysis and Epidemiology
National Center for Health Statistics
Centers for Disease Control and Prevention
3311 Toledo Road
Hyattsville, MD 20782