The NHANES survey content is determined after a rigorous evaluation process including consideration of criteria such as public health importance, feasibility of the proposed survey items and burden to survey participants. This information is important as you determine the scope of your analysis and which variables to include. For example, your analysis may require background information, such as:
- Overviews of the survey design, the target population, and data collection procedures
- Survey Contents, which shows the years components were collected and when changes to the components occurred,
- Questionnaire Instruments, and
- Examination and Lab Procedures, which is the survey protocol for obtaining the physical examination measures in the survey.
Find Survey Overviews
On any survey cycle page (e.g., NHANES 2015-2016), the Using the Data section contains links to overviews containing key background information on the overall survey and the laboratory, questionnaire, and examination components.
Find Survey Contents
On the Survey Methods and Analytic Guidelines page, scroll to the Other Resources for Analysts section and click the Survey Contents link to open the PDF file. A link to the survey contents brochure is also available on each survey cycle page (e.g., NHANES 2015-2016) in the Contents at a Glance section.
This PDF file contains tables depicting the questionnaire, examination, and laboratory components that were conducted in each survey cycle, as well as when components changed from the original sample descriptions. By reviewing this chart you can determine if the components you are interested in were collected for all the years available or only some of the years, and design your analysis accordingly.
Find Questionnaire Instruments
From any survey cycle page (e.g., NHANES 2015-2016), select the Questionnaire Instruments link in the Contents in Detail section. This page contains links to the questionnaire instruments used both in participants' homes and in the Mobile Examination Center trailers.
For example, select the Blood Pressure link under the Sample Person Questionnaire heading. This link opens to the blood pressure questions asked of the survey participants and lists possible responses. As you design your analysis, be sure to review these questions, the possible answers, and whether or not the question was part of a skip pattern.
Find Examination and Laboratory Procedures and Laboratory Methods
From any survey cycle page (e.g., NHANES 2015-2016), select the Examination and Laboratory Procedures link in the Contents in Detail section. This page contains links to the manuals documenting the procedures for various examination components.
From any survey cycle page (e.g., NHANES 2015-2016), select the Laboratory Methods link in the Contents in Detail section. This page contains links to the laboratory methods for each laboratory component.
Be sure to review the protocols as necessary.