Task 1: Introduction: How the NHANES data are linked to CMS enrollment and claims data

The linkage of NHANES respondents to their Centers for Medicare and Medicaid Services (CMS) records was performed under an interagency agreement, between the National Center for Health Statistics (NCHS), CMS, the Social Security Administration (SSA) and the Office of the Assistant Secretary for Planning and Evaluation (ASPE), and is not the responsibility of the researchers using the data. The linkage was conducted for all NHANES respondents whose linkage to CMS records was possible because they had:

  1. sufficient personally identifiable information (PII) and/or had not refused to provide their Social Security Number (SSN) or Health Insurance Claim (HIC) number and
  2. a SSN verified by the SSA Enumeration Verification System.

The survey respondents who met the above criteria were considered linkage eligible and were sent to CMS to match to the CMS Medicare Denominator file and the Medicaid Statistical Information System (MSIS) for the specific years of interest.

Info icon Information

The term eligible is being used to indicate linkage eligibility, not eligible for Medicare or Medicaid benefits entitlement. Match rate tables, indicating linkage eligibility, can be found in the resources section below.



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