From 1963 through 1996, the NHIS questionnaire was printed as a paper booklet. The interviewer read the questions and wrote the answers in the booklet. Results were subsequently keyed into a computer in preparation for data processing.
From 1997 through 2003, the NHIS used CASES software for computer-assisted personal interviewing (CAPI). The interviewer read the questions and entered the responses directly into a laptop computer.
In 2004 the NHIS questionnaire converted from CASES to BLAISE CAPI software. This technology continues to the present.
Major changes to the alcohol questions
Questions about adult alcohol use were included as special topic supplements in selected years from 1977 through 1994. The extent and content of these questions and the reference periods varied markedly from questionnaire to questionnaire. See List of Topics for specifics. In 1997, a series of questions about lifetime and current drinking status were added to the NHIS Sample Adult core questionnaire and asked annually for the duration of the 1997-2018 questionnaire design. Recodes summarizing adult drinking status have been on the data files since 2001. SAS code for creating recodes for years 1997-2000 are available on the Recodes section of this website.