Context: Selective school-based alcohol prevention programs targeting youth with personality risk factors for addiction and mental health problems have been found to reduce substance use and misuse in those with elevated personality profiles.
Objectives: To report 24-month outcomes of the Teacher-Delivered Personality-Targeted Interventions for Substance Misuse Trial (Adventure trial) in which school staff were trained to provide interventions to students with 1 of 4 high-risk (HR) profiles: anxiety sensitivity, hopelessness, impulsivity, and sensation seeking and to examine the indirect herd effects of this program on the broader low-risk (LR) population of students who were not selected for intervention.
Design: Cluster randomized controlled trial.
Setting: Secondary schools in London, United Kingdom.
Participants: A total of 1210 HR and 1433 LR students in the ninth grade (mean [SD] age, 13.7 [0.33] years).
Intervention: Schools were randomized to provide brief personality-targeted interventions to HR youth or treatment as usual (statutory drug education in class).
Main outcome measures: Participants were assessed for drinking, binge drinking, and problem drinking before randomization and at 6-monthly intervals for 2 years.
Results: Two-part latent growth models indicated long-term effects of the intervention on drinking rates (β = -0.320, SE = 0.145, P = .03) and binge drinking rates (β = -0.400, SE = 0.179, P = .03) and growth in binge drinking (β = -0.716, SE = 0.274, P = .009) and problem drinking (β = -0.452, SE = 0.193, P = .02) for HR youth. The HR youth were also found to benefit from the interventions during the 24-month follow-up on drinking quantity (β = -0.098, SE = 0.047, P = .04), growth in drinking quantity (β = -0.176, SE = 0.073, P = .02), and growth in binge drinking frequency (β = -0.183, SE = 0.092, P = .047). Some herd effects in LR youth were observed, specifically on drinking rates (β = -0.259, SE = 0.132, P = .049) and growth of binge drinking (β = -0.244, SE = 0.073, P = .001), during the 24-month follow-up.
Conclusions: Findings further support the personality-targeted approach to alcohol prevention and its effectiveness when provided by trained school staff. Particularly novel are the findings of some mild herd effects that result from this selective prevention program.
Trial registration: clinicaltrials.gov Identifier: NCT00776685.