The National Health Interview Survey (NHIS) is a continuing cross-sectional survey that is the principal source of information on the health of the civilian noninstitutionalized population of the United States. The NHIS data are collected through personal interviews that are conducted each week of the year. (Each household is interviewed once, and each week's sample is representative of the universe.) The current annual sample size is about 49,000 households and is designed to oversample black people. The sample is designed to be state-representative. The annual response rate is about 95 percent. The questionnaire consists of two basic parts: (1) a set of basic health and demographic items, and (2) one or more sets of questions on current health topics. The basic or core items are repeated each year and constitute about one-third of the questionnaire.
Age
Sex
Race
Ethnic origin
Relationship to reference person (including whether biological, adoptive, step, or foster relationship)
Marital status; whether ever married
Educational attainment
Whether attending or ever attended Head Start (for children under 6)
Place of birth (state or country)
[Note: There are no questions on citizenship.]
Work status last week
Hours worked last week
Whether usually work 35 hours or more
Reason for not working last week
Ever worked previous calendar year
Months worked
[Note: There are no questions on volunteer work or participation in work training programs.]
Earnings from all jobs and businesses last year for each adult (aged 18 or older or married)
Whether anyone in family and who received:
Wages and salaries
Self-employment income including business and farm income