Frequently Asked Questions
Physical activity is associated with improved health and reduced mortality. The NHIS is charged with monitoring progress in increasing prevalence of this important health behavior among U.S. adults.
The first questions on adult physical activity appeared on the NHIS in 1975.
No. There have been substantial changes in the conceptualization and measurement of physical activity over the years, paralleling changes in physical activity research.
No. Questions about adult physical activity are asked in other U.S. surveys, including the National Health and Nutrition Examination Survey (NHANES) and the Behavioral Risk Factor Surveillance System (BRFSS). An Explanation of U.S. Physical Activity Surveys highlights the differences among these surveys.
There are no plans to change the leisure-time physical activity questions asked in the Sample Adult Core questionnaire. Additional questions may be asked in supplement questionnaires in selected years in order to expand our understanding of this important health behavior. Such additions are contingent upon funding. The relevance of NHIS questions for physical activity epidemiology and surveillance will continue to be evaluated, and changes may be made if appropriate.
No. The existing NHIS physical activity questions, which have been in the annual core questionnaire since 1997, provide the data needed for monitoring adult physical activity prevalence specified in the 2008 Guidelines. The questions have been nearly the same since 1997 and identical since 2004.
7. I’m having trouble downloading data files for 2005 and earlier. Is there something wrong with the data?
No. The problem likely is due to using a 64-bit Microsoft operating system. NHIS Public Use data sets from 1970-2005 with the .exe file type are unable to be extracted on 64-bit computers running Microsoft operating systems. Data users are advised to rename the .exe files as .zip files and the data sets will extract correctly. This workaround is suggested for data years 1970-2005. For years 2006-2009, the .exe files do extract correctly. Beginning in 2010, NHIS data files are released as .zip files.
8. How can I get more information about NHIS physical activity data?
For further information, you may contact:
(301) 458-4901 or toll free 1-800-232-4636