Effectiveness of a school-based substance use prevention program taught by police officers in Brazil: Two cluster randomized controlled trials of the PROERD.

Background: The Drug and Violence Resistance Educational Program (PROERD) is widely disseminated and implemented as a public policy in Brazil. PROERD's current curricula are the translation of the North American program DARE-Keepin'it REAL, based on the theories of socio-emotional learning and resistance training. The present study aims to evaluate the effectiveness of PROERD in the prevention of drug use.

Method: Two PROERD curricula were analyzed through two cluster randomized controlled trials conducted with 4030 students (1727 5th graders and 2303 7th graders) in 30 public schools in São Paulo. The intervention group received ten PROERD classes delivered by trained police officers, and the control group received no intervention. Data collection was performed using self-administered questionnaires on smartphones at two points in time (baseline pre-intervention and nine months follow-up). The outcomes evaluated were initiation and recent drug use. Two different paradigms were used in a multilevel analysis: an analysis of complete cases (CC) and an intention to treat missing data through full information maximum likelihood and selection model.

Results: We found no evidence of the effectiveness of PROERD as an intervention for the prevention of drug use. For the conditional transition analysis, we found that 7th graders in the PROERD group who were already binge drinking at baseline had a significantly higher chance of maintaining this consumption pattern when compared to the control group.

Conclusion: The lack of preventive effects found here suggests that a process evaluation may address concrete implementation and cultural adaptation issues.