How Accurate Are Adolescent Reports of Drug Use?

Project ALERT (Adolescent Learning Experiences in Resistance Training) is a multiwave study that tests the effect of a drug-prevention program for seventh- and eighth-grade students. Because it relies on self-reports to obtain information on whether and how often students used cigarettes, alcohol, and marijuana, it is important to assess whether the collected data accurately represent the respondents' use. The authors examined the consistency and completeness of student responses within and across questionnaires to gain information about the reports' accuracy. They also assessed how the problems arose and what impact they might have on data bias and treatment effects analyses. Although 40 percent of students had at least one inconsistency across four waves, fewer than 2 percent committed inconsistencies that involved frequent use. The authors concluded that reporting errors do not threaten the validity of the treatment effects analysis and that the overwhelming majority of Project ALERT students accurately reported their drug use.