Task 1: Explain the Importance of Feasibility Files

Feasibility Files Overview

NCHS has created and released for public use NHANES-CMS linked data Feasibility Files. These files provide information about survey respondents’ eligibility for CMS linkage, final match status, and the years of CMS linked data files available for each successfully linked survey respondent. These files can be used to determine the maximum available sample size to assess the feasibility of conducting analyses using the CMS Medicare and Medicaid linked data. These files make it possible to identify demographic and health status variables collected in the survey that may be of interest in subdividing the survey sample, calculating estimates of numbers of people in categories of interest, and determining cell sizes by related categories. This process establishes the likelihood that there will be sufficient numbers of individuals and a sufficient number of degrees of freedom (see Continuous NHANES tutorial for key concepts about degrees of freedom) in the category of interest who have been successfully linked to CMS data for your NCHS Research Data Center proposal.

Why the Feasibility Files are Necessary

The feasibility files should be merged with the public use NHANES datasets to provide a limited set of variables that can be used to determine the maximum available sample size for each linked file.

It is important to note that the variables proposed for this data file do not contain any information about Medicare or Medicaid benefits or payments.  They simply provide record status variables which enable researchers to gauge whether their analytic samples will have sufficient numbers of sample persons with CMS linked data to warrant an application to the RDC. 


Continuous NHANES Web Tutorial: Key concepts about degrees of freedom

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