Objective: This study assesses the impact of a school-based drug prevention program, called Project ALERT, on risky sexual behavior among 1901 nonmarried, sexually active young adults who participated in one of two program variations as adolescents. It also tests for differences in program effect depending on program duration (middle school only vs. a combined middle school and high school program) and participants' gender.
Methods: Using survey data from a randomized controlled experiment conducted in 45 midwestern communities (55 schools), we assessed program effects on risky sexual behavior at age 21 with three measures-having unprotected sex because of drug use plus engaging in inconsistent condom use and having sex with multiple partners.
Results: Compared to control, Project ALERT reduced the likelihood of all risky sex outcomes except inconsistent condom use among these sexually active young adults, effects that occurred 5 and 7 years after program exposure. Program effects were partially mediated by reductions in alcohol and drug abuse. There were no significant differences in program effects by gender or by program duration compared to control. Implications for future prevention programs and research are discussed.