Juliana Y Valente1, Hugo Cogo-Moreira2, Zila M Sanchez3. 1. Department of Preventive Medicine, Universidade Federal de São Paulo, São Paulo, Brazil. 2. Department of Psychiatry, Universidade Federal de São Paulo, São Paulo, Brazil; Department of Psychology and Education, Freie Universität Berlin, Berlin, Germany. 3. Department of Preventive Medicine, Universidade Federal de São Paulo, São Paulo, Brazil. Electronic address: zila.sanchez@unifesp.br.
Abstract
BACKGROUND: The aim of the present study was to evaluate a formal mediation analysis effect of the #Tamojunto program on adolescents' drug use and violent behavior in schools through decision-making skills using a potential outcomes approach. METHODS: An in-cluster randomized controlled trial was conducted in 2014-2015 with 6691 7th- and 8th-grade students in 72 public schools in 6 Brazilian cities to evaluate the effects of the European drug prevention program Unplugged, called #Tamojunto in Brazil. Baseline data were collected prior to program implementation, and follow-up data were collected 9 and 21 months later. Mediation analysis using a potential outcomes approach, in which counterfactuals are modeled if positivity is met, was used to evaluate the indirect effects of the program #Tamojunto on the third-wave of drug use (alcohol, tobacco, marijuana, inhalants, and binge drinking) and school violence (bullying or physical, verbal and sexual aggression) assessment through decision-making skills. RESULTS: When controlling for all covariates, the Total Natural Indirect Effect (TNIE) was significant only for past-year drug use (TNIE = 0.003, 95%CI = 0.001; 0.007). In the adjusted models, 37.5% of the effect of the intervention on drug use was mediated by decision-making skills. CONCLUSIONS: The #Tamojunto program increased drug use through decreasing decision-making skills. The findings demonstrate that this program changes decision-making skills but in the opposite direction proposed by the theoretical model of the program, suggesting that modifications are needed to produce the intended effect of the program.
RCT Entities:
BACKGROUND: The aim of the present study was to evaluate a formal mediation analysis effect of the #Tamojunto program on adolescents' drug use and violent behavior in schools through decision-making skills using a potential outcomes approach. METHODS: An in-cluster randomized controlled trial was conducted in 2014-2015 with 6691 7th- and 8th-grade students in 72 public schools in 6 Brazilian cities to evaluate the effects of the European drug prevention program Unplugged, called #Tamojunto in Brazil. Baseline data were collected prior to program implementation, and follow-up data were collected 9 and 21 months later. Mediation analysis using a potential outcomes approach, in which counterfactuals are modeled if positivity is met, was used to evaluate the indirect effects of the program #Tamojunto on the third-wave of drug use (alcohol, tobacco, marijuana, inhalants, and binge drinking) and school violence (bullying or physical, verbal and sexual aggression) assessment through decision-making skills. RESULTS: When controlling for all covariates, the Total Natural Indirect Effect (TNIE) was significant only for past-year drug use (TNIE = 0.003, 95%CI = 0.001; 0.007). In the adjusted models, 37.5% of the effect of the intervention on drug use was mediated by decision-making skills. CONCLUSIONS: The #Tamojunto program increased drug use through decreasing decision-making skills. The findings demonstrate that this program changes decision-making skills but in the opposite direction proposed by the theoretical model of the program, suggesting that modifications are needed to produce the intended effect of the program.