Percentage distributions provided in the codebook were generated using full weights, which are not available on the public use files. Therefore, these results cannot be replicated using the public use files. The differences between results produced using the full weights and those produced using the sampling weights available on the public use files are estimated to be below 1 percent. To protect the confidentiality 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. 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.

Multistate 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 74 PSUs, 12 were selected with certainty and 62 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).

This is the ninth annual survey in this series that explores changes in important values, behaviors, and lifestyle orientations of contemporary American youth. The students are randomly assigned one of five 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 1,300 variables across the questionnaires. Full details on the research design and procedures, sampling methodology, content areas, and questionnaire design, as well as percentage distributions by respondent's sex, race, region, college plans, and drug use, appear in the annual ISR volumes MONITORING THE FUTURE: QUESTIONNAIRE RESPONSES FROM THE NATION'S HIGH SCHOOL SENIORS.

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..

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

Response Rates: The participation rate among schools has been between 66 and 80 percent since the inception of the study. The overall student response rate for 1983 was 84 percent.

High school seniors in the contiguous United States.

Monitoring the Future (MTF) Series