National Health and Nutrition Examination Survey


If you are eligible to participate, your name will not be associated with your answers.  Your responses are voluntary, confidential, and will be used to understand the nation’s health. All data are combined to protect the confidentiality of all participants in NHANES. In addition, NHANES databases are password protected and encrypted and can only be accessed by appropriate personnel. The data collected are used for research and statistical purposes only. No information that could identify any individual is publicly released.


How do you keep my information secure?

The National Center for Health Statistics (NCHS) is committed to protecting your privacy. There are many procedures in place to prevent the disclosure of your data to others. More information on confidentiality can be found in our Confidentiality Brochure pdf icon[PDF – 68 KB].

Image of doctor and patient

Who can I contact if I have questions?

To discuss the survey or to speak to our Senior Medical Officer, call us at 1-800-452-6115. If you have questions about your rights as a survey participant, call the Research Ethics Review Board at the National Center for Health Statistics at 1-800-223-8118. Leave a brief message containing your name, phone number, and your NHANES concerns. Your call will be returned as soon as possible.
Thank you.

Division of National Health and Nutrition Examination Survey
National Center for Health Statistics
Centers for Disease Control and Prevention
3311 Toledo Road
Hyattsville, MD 20782
(800) 452-6115

Page last reviewed: October 19, 2018