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 with the 1997 data collection. The present collection consists of the basic module only, plus additional household data. The basic module corresponds to the former NHIS core questionnaire and is made up of the family core, the sample adult core, and the sample child core questions. Each record in the Household-Level File (Part 1) contains information on the type of living quarters, number of families in the household responding and not responding, and the month and year of the interview for each eligible sampling unit. The Family-Level File (Part 2) 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, the Person-Level File (Part 3) provides information on all family members with respect to health status, limitation of daily activities, cognitive impairment, and health conditions. Also included are data on years at current residence, region variables, height, weight, bed days, doctor visits, hospital stays, and health care access and utilization. Episode-based information is found in the Injury Episode File (Part 4), while the Poison Episode File (Part 5) examines the cause and date of injury or poisoning, loss of time from work or school, and whether the poisoning resulted in hospitalization. Information in the Injury Verbatim File (Part 6) is comprised of narrative text describing injuries, including type of injury, how the injury occurred, and the body part injured. A randomly-selected adult in each family was interviewed for the Sample Adult File (Part 7) regarding respiratory conditions, renal conditions, AIDS, and joint symptoms, along with questions regarding health status, limitation of daily activities, and behaviors such as smoking, alcohol consumption, and physical activity. The Sample Child File (Part 8) provides information from a knowledgeable adult in the household on medical conditions of one child in the household, such as respiratory problems, seizures, allergies, and use of special equipment such as hearing aids, braces, or wheelchairs. Also included are questions regarding child behavior and the use of mental health services. The Child Immunization File (Part 9) presents information from shot records and supplies vaccination status, along with the number and dates of shots, and information about chicken pox vaccines.

(1) Users should refer to the codebook for a detailed description of the changes implemented for the 1997 NHIS. (2) The data from the Household-Level File can be merged with any of the other files, and other files can be merged as well. For further information on merging data, consult the codebook. (3) The periodic module is not yet available from NCHS. When released, it will provide more detailed information on topics resulting from the basic module. The topical module, when released, will correspond to the supplements of the 1982-1996 NHIS and will focus on public health data needs as they arise. (4) Per agreement with NCHS, ICPSR distributes the data files and text of the technical documentation in this collection in their original form as prepared by NCHS. (5) The codebooks, coding manual, and data collection instruments are provided by ICPSR as Portable Document Format (PDF) files. The PDF file format was developed by Adobe Systems Incorporated and can be accessed using PDF reader software, such as the Adobe Acrobat Reader. Information on how to obtain a copy of the Acrobat Reader is provided on the ICPSR Web site.

The NHIS uses a stratified multistage probability design. The sample for the NHIS is redesigned every decade using population data from the most recent decennial census. A redesigned sample was implemented in 1995. This new design includes a greater number of primary sampling units (PSUs) (from 198 in 1994 to 358), and a more complicated nonresponse adjustment based on household screening and oversampling of Black and Hispanic persons, for more reliable estimates of these groups.

Datasets: DS0: Study-Level Files DS1: Household-Level File DS2: Family-Level File DS3: Person-Level File DS4: Injury Episode File DS5: Poison Episode File DS6: Injury Verbatim File DS7: Sample Adult File DS8: Sample Child File DS9: Child Immunization File

Civilian, noninstitutionalized population of the 50 states and the District of Columbia.