The National Health and Nutrition Examination Survey (NHANES) is designed to assess the health and nutritional status of adults and children in the United States. The survey is unique in that it combines interviews with standardized physical examinations and laboratory tests.

NHANES was conducted on a periodic basis from 1971 to 1994, including NHANES I (1971-1975), NHANES II (1976-1980), NHANES III (1988-1994), and a Hispanic Health and Nutrition Examination Survey (HHANES, 1982-1984). In 1999, NHANES became continuous and has been collecting data annually ever since.

All of the NHANES programs utilized a stratified, multistage probability cluster design to provide a nationally representative sample of the U.S. civilian, noninstitutionalized population. The NHANES interview includes demographic, socioeconomic, dietary, and health-related questions. The examination component conducted in a mobile examination center consists of medical, dental, and physiological measurements, as well as the collection of biospecimens, such as blood and urine for laboratory testing.

This set of restricted data contains indirect identifying and/or sensitive information collected in NHANES prior to 1999. Please refer to the links below for additional data available from NHANES:

• NHANES Public Use Data at: https://wwwn.cdc.gov/nchs/nhanes/Default.aspx


• NHANES Restricted Data: 1999 - present at: https://data.cdc.gov/dataset/National-Health-and-Nutrition-Examination-Survey-N/9ixb-fwvy


• NHANES Genetic Restricted Data at: https://data.cdc.gov/dataset/National-Health-and-Nutrition-Examination-Survey-N/hdx4-e4uu


• NHANES National Youth Fitness Survey (NNYFS) Restricted Data at: https://data.cdc.gov/dataset/3-NHANES-National-Youth-Fitness-Survey-NNYFS-Restr/5u84-m4rs

Please refer to the NHANES - National Health and Nutrition Examination Survey Homepage at: https://www.cdc.gov/nchs/nhanes/index.htm for further details on the NHANES design, implementation, and data analysis.

The National Health and Nutrition Examination Survey’s (NHANES) National Youth Fitness Survey (NNYFS) was conducted in 2012 to collect nationally representative data on physical activity and fitness levels for U.S. children and adolescents aged 3-15 years, through household interviews and fitness tests conducted in mobile examination centers.

The NNYFS interview includes demographic, socioeconomic, dietary, and health-related questions. The fitness tests included standardized measurements of core, upper, and lower body muscle strength, and gross motor skills, as well as a measurement of cardiovascular fitness by walking and running on a treadmill. A total of 1,640 children and adolescents aged 3-15 were interviewed and 1,576 were examined.

This set of restricted data files contains indirect identifying and/or sensitive information collected in NNYFS. For NNYFS public use files, please visit NNYFS 2012 at: https://wwwn.cdc.gov/nchs/nhanes/search/nnyfs12.aspx.
For more information on the survey design, implementation, and data analysis, see the NNYFS Analytic Guidelines at: https://www.cdc.gov/nchs/nnyfs/analytic_guidelines.htm.
For more information on NHANES, visit the NHANES - National Health and Nutrition Examination Survey Homepage at: https://www.cdc.gov/nchs/nhanes/index.htm.