National Health Interview Survey, 2009 (ICPSR 28721)
Published: Aug 26, 2010
The purpose of the National Health Interview Survey (NHIS) is to obtain information about the amount and distribution of illness, its effects in terms of disability and chronic impairments, and the kinds of health services people receive. Implementation of a redesigned NHIS, consisting of a basic module, a periodic module, and a topical module, began in 1997 (see NATIONAL HEALTH INTERVIEW SURVEY, 1997 [ICPSR 2954]). The 2009 NHIS contains the Household, Family, Person, Sample Adult, and Sample Child files from the basic module. Each record in Part 1, Household Level, contains data on type of living quarters, number of families in the household responding and not responding, and the month and year of the interview for each sampling unit. Part 2, Family Level, is made up of reconstructed variables from the person-level data of the basic module and includes information on sex, age, race, marital status, Hispanic origin, education, veteran status, family income, family size, major activities, health status, activity limits, and employment status, along with industry and occupation. As part of the basic module, Part 3, Person Level, provides information on all family members with respect to health status, limitation of daily activities, cognitive impairment, and health conditions. Also included are variables related to doctor visits, hospital stays, and health care access and utilization. A randomly-selected adult in each family was interviewed for Part 4, Sample Adult Level, regarding respiratory conditions, renal conditions, AIDS, joint symptoms, health status, limitation of daily activities, and behaviors such as smoking, alcohol consumption, and physical activity. Part 5, Sample Child Level, provides information from an adult in the household on medical conditions of one child in the household, such as respiratory problems, seizures, allergies, and use of special equipment like hearing aids, braces, or wheelchairs. Part 6, Injury/Poison Episode, is an episode-based file that contains information about the external cause and nature of the injury or poisoning episode and what the person was doing at the time of the injury or poisoning episode, in addition to the date and place of occurrence. Part 7, Injury/Poison Episode Verbatim, contains edited narrative text descriptions of the injury or poisoning, provided by the respondent. Part 8, Disability Questions Tests 2008/2009, provides information pertaining to four key areas of disability: Vision, hearing, mobility, and cognintive functioning. The data for Part 8 were collected over the span of five calendar quarters from October 2008 through the end of 2009. Part 9, Paradata, does not contain health related information, but rather data which are related to the interview process, including measures of time, contact-ability, and cooperation.
In preparing the data files for this collection, the National Center for Health Statistics (NCHS) removed direct identifiers and characteristics that might lead to identification of data subjects. As an additional precaution, NCHS requires, under Section 308(d) of the Public Health Service Act (42 U.S.C. 242m), that data collected by NCHS not be used for any purpose other than statistical analysis and reporting. NCHS further requires that analysts not use the data to learn the identity of any persons or establishments and that the director of NCHS be notified if any identities are inadvertently discovered. ICPSR member institutions and other users ordering data from ICPSR are expected to adhere to these restrictions.
2009 (Fourth Quarter 2008-Fourth Quarter 2009)
Date of Collection
2009 (Fourth Quarter 2008-Fourth Quarter 2009)
Data Collection Notes
Beginning in 2005, the NHIS no longer allows an emancipated minor (someone between the ages of 14 and 17 living on their own without supervision of an adult family member or legal guardian) to be an eligible respondent or a sample adult or sample child. An emancipated minor is not eligible to be the respondent for the Sample Child questionnaire even if they are the parent of the sample child.
The User Guide contains information regarding the merging of files and the use of weight variables, along with information regarding changes to the 2009 NHIS.
To learn more about the National Health Interview Survey, visit the Centers for Disease Control and Prevention (CDC) Web site. At that site you can join the HISUSERS e-mail list by providing your name and e-mail address, selecting the item, "National Health Interview Survey (NHIS) researchers", and clicking on "subscribe".
Analysts should be aware that 317 persons who were active duty members of the Armed Forces at time of interview are on the Person-Level file and will appear in the unweighted frequencies, despite the fact that NHIS covers only the civilian noninstitutionalized household population. These active duty members of the Armed Forces are included in that file because at least one other family member is a civilian eligible for the survey. The value of the final annual person weight (WTFA) for these military persons is zero, so they will not be counted when making national (i.e., weighted) estimates.
Questionnaires have been provided in both English and Spanish.
The NHIS uses a stratified multistage probability design. Oversampling of the Black and Hispanic populations has been retained in 2009 to allow for more precise estimation of health characteristics in these growing minority populations. The new sample design also oversamples the Asian population.
Civilian, noninstitutionalized population of the 50 states and the District of Columbia.
Mode of Data Collection
computer-assisted personal interview (CAPI)
Original Release Date
2010-08-26 The documentation has been updated to reflect the most current available documentation from the NCHS. Additionally, the Sample Adult Level (Part 0004) data files have been updated.
2010-07-13 ICPSR data undergo a confidentiality review and are altered when necessary to limit the risk of disclosure. ICPSR also routinely creates ready-to-go data files along with setups in the major statistical software formats as well as standard codebooks to accompany the data. In addition to these procedures, ICPSR performed the following processing steps for this data collection:
- Created variable labels and/or value labels.
- Created online analysis version with question text.
The public-use data files in this collection are available for access by the general public. Access does not require affiliation with an ICPSR member institution.
This study is maintained and distributed by the National Archive of Computerized Data on Aging (NACDA), the aging program within ICPSR. NACDA is sponsored by the National Institute on Aging (NIA) at the National Institutes of Heath (NIH).