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National Nursing Home Survey (NNHS) and National Nursing Assistant Survey (NNAS) Restricted Variables


Restricted data fields are information that could compromise the confidentiality of survey respondents or institutions, or are sensitive by nature. If researchers interested in using data from a survey find that something asked on the survey questionnaire does not have a corresponding variable in the public use data set, that variable may be restricted.

The following links take you to information about restricted variables in the 2004 National Nursing Home Survey and the National Nursing Assistant Survey. These variables are either not in public use files or are presented in different form in the public use files. Using restricted variables requires the submission of a research proposal to the National Center for Health Statistics’ (NCHS) Research Data Center for access.

NNHS and NNAS can be merged using restricted ID variables. For example, the patient, facility, and nursing assistant worker files from NNHS can be linked using restricted variables. This allows researchers to examine the relationships between facility characteristics, patient characteristics, and workers’ characteristics.

2004 National Nursing Home Survey - Facility File [PDF - 64 KB]

2004 National Nursing Home Survey - Current Resident File [PDF - 49 KB]

2004 National Nursing Assistant Survey [PDF - 50 KB]

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