Multistage area probability sample design involving five
selection stages: (1) primary sampling unit (PSU) areas (e.g., counties), (2) subareas within primary areas (e.g., blocks or block groups), (3) listing units within subareas, (4) age domains within sampled listing units, and (5) eligible individuals within sampled age domains. The 1997 NHSDA used the same 115 PSUs as the 1995 and 1996 NHSDAs, plus a total of 18 supplemental PSUs from Arizona and
California. The 115 PSUs were selected to represent the nation's total eligible population, including areas of high Hispanic concentration. These PSUs were defined as metropolitan areas, counties, groups of counties, Census tracts, and independent cities. Of the 115 PSUs, 43 were selected with certainty and 72 were randomly selected with
probability proportional to size (PPS). The national sample was supplemented by a PPS selection of 14 noncertainty PSUs from Arizona plus 4 noncertainty PSUs from California. Because the national sample provided representation for certainty PSUs in each state, no additional certainty PSUs were added to either sample. Unlike NHSDAs prior to 1996, the 1996 and 1997 NHSDAs did not oversample cigarette
smokers aged 18-34. Unlike the 1996 NHSDA, which reused about 95 percent of the sample segments used in 1995, the 1997 NHSDA basically surveyed a new segment sample. Only 96 segments in the 1997 NHSDA overlapped with 1996 segments. Beginning in quarter two of the 1997 NHSDA, residents of Arizona and California were oversampled to provide
direct survey estimates for these states. Due to confidentiality concerns, there is no variable on the public use data file to indicate a state identifier. The five age groups were: ages 12-17, 18-25, 26-34, 35-49, and 50 and older. The three race/ethnic groups were: Whites/others, non-Hispanic Blacks, and Hispanics. Blacks and Hispanics were oversampled. The study yielded an 85.0 percent
eligibility rate for sample households and a 92.7 percent completion rate for screening eligible households.
The civilian, noninstitutionalized population of the
United States aged 12 and older, including residents of
noninstitutional group quarters, such as college dormitories, group homes, shelters, rooming houses, and civilians dwelling on military installations.
personal interviews and self-enumerated answer sheets
The interview response rates for the three racial/ethnic groups were: 75.5 percent for Whites/others, 81.8
percent for Blacks, and 82.5 percent for Hispanics. The overall unweighted interview response rate was 78.3 percent. A completed interview had to contain, at a minimum, data on the recency of use of marijuana, cocaine, and alcohol.