Background and aims: The Örebro Prevention Programme (ÖPP) was found previously to be effective in reducing drunkenness among adolescents [Cohen’s d=0.35, number needed to treat (NNT)=7.7]. The current study tested the mediating role of parents’ restrictive attitudes to underage drinking in explaining the effectiveness of the ÖPP, and the potential moderating role of gender, immigration status, peers’ and parents’ drinking and parent–adolescent relationship quality.
Design: A quasi-experimental matched-control group study with assessments at baseline, and at 18- and 30-month follow-ups. Participants of the 895 target youths at ages 12–13 years, 811 youths and 651 parents at baseline, 653 youths and 524 parents at 18-month and 705 youths and 506 parents at 30-month follow-up participated in the study.
Measurements: Youths reported on their past month drunkenness, their parents’ and peers’ alcohol use and the quality of their relationship with parents. Parents reported on their attitudes to underage drinking.
Findings: The mediation analyses, using latent growth curve modeling, showed that changes in parents’ restrictive attitudes to underage drinking explained the impact of the ÖPP on changes in youth drunkenness, which was reduced, and onset of monthly drunkenness, which was delayed, relative to controls. Mediation effect explained 57 and 45%of the effects on drunkenness and onset of monthly drunkenness, respectively. The programme effects on both parents’ attitudes and youth drunkenness were similar across gender, immigrant status, parents’ and peers’ alcohol use and parent–youth relationship quality.
Conclusions: Increasing parents’ restrictive attitudes to youth drinking appears to be an effective and robust strategy for reducing heavy underage drinking regardless of the adolescents’ gender, cultural origin, peers’ and parents’ drinking and relationship quality with parents.