Throughout the years, NHANES datasets and related information have been released in a variety of formats and different media. However, since the late 1990s, all publicly available data and related documentation are released and updated in a centralized location: the NHANES website.
Datasets contain data for persons who participated in the selected survey. The National Health and Nutrition Examination Survey (NHANES) datasets are labeled by cycle year. The website contains the public-use data files for each of National Center for Health Statistic's national surveys starting with the initial National Health Examination Survey (NHES) I dataset up to the most current dataset. Codebooks and documentation are part of each data file. (For more experience on locating data files and related documentation, please see the Locate Variables module and the Download Data Files module.)
There are several pages of downloads to review.
This layout only applies to the most Continuous NHANES datasets starting from 1999. Datasets earlier than 1999 will have a different format and layout.
High quality data is released according to these guiding principles:
while maintaining survey participant confidentiality.
As a result, some variables or entire data files are not publicly released due to disclosure concerns, for example, geographic identifiers. These files are only available through the Research Data Center (RDC). You may review the Data Release and Access Policy for more information. For some non-publicly released data, the documentation, including a codebook with frequencies, is available to assist data users preparing proposals to use the Research Data Center.