What is the National Health Interview Survey?
- The National Health Interview Survey (NHIS) is a national survey conducted by the U.S. Census Bureau on behalf of the National Center for Health Statistics (NCHS). The National Health Interview Survey (NHIS) is the principal source of information on the health of the civilian noninstitutionalized population of the United States and is one of the major data collection programs of the National Center for Health Statistics (NCHS), which is part of the U.S. Centers for Disease Control and Prevention (CDC).
- NHIS data are collected through personal household interviews. For over 50 years, interviewers from the U.S. Census Bureau have visited American homes to ask about a broad range of health topics. Survey results have been instrumental in providing data to track health status, health care access, and progress toward achieving national health objectives.
Why is this survey important?
- The main objective of the NHIS is to monitor the health of the U.S. population through the collection and analysis of data on a broad range of health topics such as medical conditions, health insurance, doctor’s office visits, physical activity and other health behaviors.
- The National Health Interview Survey data is used to monitor progress towards national health objectives, evaluate health policies and programs, and track changes in health behaviors and health care use.
- Government agencies, universities, private health planners and researchers use the data to identify and work on significant health problems. The data are also used to determine how best to use available dollars and personnel to solve these health problems.
What is the legal authority for conducting this survey?
Congress authorized the NHIS data collection in Section 306 of the Public Health Service Act (42 United States Code 242k). The U.S. Census Bureau is conducting this survey on behalf of the National Center for Health Statistics (NCHS) under the authority of Title 13, United States Code (U.S.C.), Section 8(b).
What should you expect if your address was randomly selected to be in the survey?
- A household selected for the National Health Interview Survey will first receive a letter from the director of the National Center for Health Statistics. The letter provides information about the survey and informs the resident(s) that they can expect to be contacted by a Census Bureau interviewer in the near future.
- The Census Bureau interviewer will conduct the interview at the respondent’s convenience. That means, if the respondent works, we will conduct the interview after business hours or on the weekend. If daytime is preferable, we can accommodate that time as well. The survey takes an average of about an hour to do all the parts, depending on the size and health of family members.
- The survey covers a wide range of topics like doctor visits, medical conditions, health insurance, physical activity, and injuries. We also ask questions that help us better understand the health information you give us. For example, we ask about race, income, and permission to combine your answers with information from other places, like medical records. Most people have no difficulty with any of the questions in the NHIS. However, others find some questions to be sensitive. You do not have to answer any questions you don’t want to.
How was I selected to be in this survey?
The Census Bureau selected addresses across the entire U.S. using scientific methods so that they represent all communities in the U.S. Your household was selected to represent thousands of other households like yours. We cannot select anyone else if you do not participate, which may mean that households like yours are underrepresented in national estimates. These estimates are used by policy makers to determine needs for health services in our country. By participating, you perform a valuable public service for your family, community, and country.
How can I verify that my address was selected for this survey?
If you wish to verify that your address was selected for this survey, you can contact your Census Bureau Regional Office and they can verify for you whether your address was selected for a particular survey (see the map for contact information.)
How can I verify that the person contacting me is a Census Bureau employee?
- All Census Bureau employees identify themselves by name and carry a badge identifying him/her as a U.S. Census Bureau employee. They will be carrying a laptop with the Census Bureau logo on it to conduct the survey.
- If you receive a call and wish to verify that the caller is a Census Bureau employee, you can call one of our regional offices or you can use the staff search on our website.
I am not sick – Why should I take part in a health survey?
This is a survey of the Nation’s health. We want to know how many people are sick and why they are sick. We also want to know how many people are healthy and what makes them healthy. Everyone’s answers are important.
Is participation mandatory?
Survey participation is voluntary; however, we cannot select anyone else to replace you if you were selected and do not participate, which may mean that households like yours are underrepresented in national estimates.
Can I be identified by my responses?
- NCHS collects and uses information you provide in accordance with System of Records Notice 09-20-0164, Health and Demographic Surveys Conducted in Probability Samples of the United States.
How do I know my responses are safe?
The responses that are collected from surveys conducted by the Census Bureau field representatives and contact center staff are encrypted both in transit and at rest on the Census Bureau’s servers. These servers are part of a stand-alone network that is not accessible by the Internet. These servers are constantly monitored for any signs of intrusions.
Where can I find the statistics produced by this survey?
- Data from the NHIS, including your contribution if you participated in the survey, are collected into microdata files that are edited to remove all personal identifiers. These edited files are released to the public through the NHIS website. The data from these files are also statistically analyzed, and the results are published in several types of reports that are released over the Internet or in journal articles.
- The collected data are used for research and statistical purposes only. When analytical reports are prepared and released by NCHS staff, individual answers have been combined with those of many other respondents, which safeguards the privacy of the individuals who responded to the survey. No information that could identify any individual is publicly released.
- More information about the available microdata files and reports is found on the NHIS website.
What if I have additional questions, recommendations, or issues that I need resolved?
- If you have additional questions about the survey, or if you wish to speak to someone at the Census Bureau, you can contact the respondent advocate. The respondent advocate can address the concerns of those households that have been selected to participate in this survey, as well as share that feedback with those who manage the survey operations.