Does the Brazilian version of the strengthening families program (Familias Fortes) reduce adolescent substance use and change parental behavior? Evidence from a 2-year follow-up study

Abstract

Background

The Brazilian adaptation of the Strengthening Families Program (SFP), known as Famílias Fortes (FF-BR 10–14), has demonstrated positive short-term effects on parental behavior. This study aims to evaluate the 12- and 24-month follow-ups of the FF-BR 10–14, focusing on parental outcomes and substance use prevention.

Methods

This is a parallel-cluster randomized controlled trial (RCT) involving 1610 participants (805 adolescents aged 10–14 and 805 caregivers). Conducted across 60 Social Assistance Reference Centers (SARC) in 12 municipalities in Brazil, the trial evaluates the effectiveness of the FF-BR 10–14 program. This study presents data collected at three time points: baseline, 12 and 24 months of follow-up. Multilevel mixed-effects models assessed the program effects on parental and adolescent outcomes (drug use and family behavior), with adjustments for sociodemographic factors.

Results

The results reveal no statistically significant differences between the groups in terms of adolescent drug use after either follow-up. However, participating in the program shows a reduction in negligent parental style (aOR 0.46, 95%CI 0.22;0.97), parental binge drinking (aOR 0.24, 95%CI 0.08; 0.74), as well as an increase in parental ability to set clear rules regarding their children’s drug use (β 0.43, 95%CI 0.03; 0.83) and an improvement in adolescents’ skills to resolve family conflicts (β 0.79, 95%CI 0.11; 1.46) and to manage stress (β 0.65, 95%CI 0.16; 1.15).

Conclusion

The Famílias Fortes program shows positive effects on mediators, such as parenting practices and adolescent coping skills, but not on the primary outcomes of adolescent substance use. These findings highlight the program’s role in improving the family environment and supporting prevention efforts through intermediary behaviors.

Trial registration

The study was registered in the Brazilian Ministry of Health Register of Clinical Trials (REBEC), under protocol no. RBR-5hz9g6z (https://ensaiosclinicos.gov.br/rg/RBR-5hz9g6z) - July 8th, 2022.