self-enumerated questionnaire (1) To protect the anonymity of respondents, all variables that could be used to identify individuals have been collapsed or recoded on the public use files. These modifications should not affect analytic uses of the public use files. (2) Variables omitted from the Western region questionnaires are noted in each codebook. (3) Users are advised that there are seven parts to the collection: one containing the "key" or core questions for all six questionnaires and a separate part for each of the six different questionnaire forms. The core file consists of all respondents for all six questionnaires, however, only those variables that appear on all six questionnaires and demographic variables are found in this file. The core file consists primarily of drug use data and demographic variables. (4) The collection is documented by machine-readable codebooks with a separate codebook for each part. Users are further advised to consult the appropriate MONITORING THE FUTURE: QUESTIONNAIRE RESPONSES FROM THE NATION'S HIGH SCHOOL SENIORS annual volume, available from the Monitoring the Future staff, for more information about the collection. MTF does not release detailed geography codes in its public use files because of the disclosure risk it would cause. The MTF sample is drawn to generate representative samples of the four Census Bureau regions of the country (Northeast, Midwest, South, and West), but it does not generate representative samples of smaller geographic areas such as states, counties, or cities. For additional information about data that is withheld from the public use files please contact MTF directly at mtfinformation@umich.edu.

Multistage area probability sample design involving three selection stages: (1) geographic areas or primary sampling units (PSUs), (2) schools (or linked groups of schools) within PSUs, and (3) students within sampled schools. Of the 80 PSUs, 8 were selected with certainty and 72 were selected with probability proportionate to size based on the size of the senior class. In schools with more than 400 seniors, a random sample of seniors or classes was drawn. In schools with less than 400 seniors, all seniors were asked to participate. Each school was asked to participate for two years so that each year one-half of the sample is replaced. Schools refusing participation were replaced with similar schools in terms of geographic location, size, and type of school (e.g., public, private/Catholic, private/non-Catholic). The total sample was divided into six subsamples consisting of an average of 2,700 respondents, and each subsample was administered a different form of the questionnaire, although all respondents answered the "core" drug and demographic questions. The participation rate among schools has been between 66 and 80 percent since the inception of the study. The overall student response rate for 1998 was 82 percent.

This is the 24th annual survey in this series that explores changes in important values, behaviors, and lifestyle orientations of contemporary American youth. Students are randomly assigned to complete one of six questionnaires, each with a different subset of topical questions but all containing a set of "core" questions on demographics and drug use. There are about 1,400 variables across the questionnaires. Drugs covered by this survey include tobacco, alcohol, marijuana, hashish, LSD, hallucinogens, amphetamines (stimulants), Ritalin (methylphenidate), quaaludes, barbiturates (tranquilizers), cocaine, crack, and heroin. Other items include attitudes toward religion, parental influences, changing roles for women, educational aspirations, self-esteem, exposure to drug education, and violence and crime -- both in and out of school.

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 online analysis version with question text.; Checked for undocumented or out-of-range codes..

Datasets: DS0: Study-Level Files DS1: Core Data DS2: Form 1 Data DS3: Form 2 Data DS4: Form 3 Data DS5: Form 4 Data DS6: Form 5 Data DS7: Form 6 Data

High school seniors in the contiguous United States.

Monitoring the Future (MTF) Series