Questions are also asked about perceived risks associated with using illegal drugs, the actual health and behavioral consequences of use, and the availability of drugs. In early waves of the survey, respondents were asked to specify the amount and cost of marijuana and cocaine consumed within the past 30 days. However, these consumption and expenditure questions have not been asked since the early 1990s.
Given the sensitive nature of the questions posed, substantial resources are devoted to eliciting accurate responses. The surveys are conducted by face-to-face interviews in the home or at a private location, if possible. Various steps are taken to ensure confidentiality and anonymity, but frequently this is not possible for respondents ages 12–17 (U.S. General Accounting Office, 1993).1
Monitoring the Future (MTF) is an ongoing annual study of students in public and private schools in the United States based on a sample developed using a multistage random selection procedure. It assesses the prevalence of and trends in self-reported drug use among school students. It also asks questions concerning peer norms regarding drugs, beliefs about the dangers of illegal drugs, and perceived availability of drugs (Johnston et al., 1993, 1998). Illegal drugs, alcohol, tobacco, psychoactive pharmaceuticals (non-medical use), and inhalants are included. Students who have dropped out of high school (about 15 percent of those who enter) are not surveyed.
The University of Michigan’s Institute for Social Research has conducted the survey each year since 1975. The survey initially focused on high school seniors but expanded to include 8th and 10th grade students in 1991. In 2000, 13,286 12th grade students were surveyed in 134 schools. Sample sizes for students in 8th and 10th grades were 17,311 (156 schools) and 14,576 (145 schools), respectively.
The MTF instrument includes questions about the drug use of student respondents. For each drug, the survey elicits information on the frequency of use within the respondent’s lifetime, past year, and past 30
Prior to the interview, respondents are repeatedly assured that their identities will be handled with utmost care in accordance with the federal law. During the interview, the respondent responds to sensitive questions, including those on drug use. The interviewer neither sees nor reviews the answers to those questions. After the answer sheet is complete, the respondent places them in an envelope that is then sealed and mailed, with no personal identifying information attached, to the Research Triangle Institute. Interviews are designed to be conducted in private settings, with only the interviewer and respondent present. Often, however, the interview is not completely private—especially for respondents ages 12 to 17. According the Office of Applied Statistics of the Substance Abuse and Mental Health Services Administration, at least 40 percent of the interviews with respondents in this age group are not completely private.