Aims: This study aimed to assess the effectiveness of the Örebro prevention programme (ÖPP), an alcohol misuse prevention programme that aims to reduce youth drinking by changing parental behaviour.
Design: Cluster-randomized trial, with schools assigned randomly to the ÖPP or no intervention.
Setting: Forty municipal schools in 13 counties in Sweden.
Participants: A total of 1752 students in the 7th grade and 1314 parents were assessed at baseline. Students' follow-up rates in the 8th and 9th grades were 92.1% and 88.4%, respectively.
Measurements: Classroom questionnaires to students and postal questionnaires to parents were administered before randomization and 12 and 30 months post-baseline.
Findings: Two-level logistic regression models, under four different methods of addressing the problem of loss to follow-up, revealed a statistically significant programme effect for only one of three drinking outcomes under one loss-to-follow-up method, and that effect was observed only at the 12-month follow-up.
Conclusions: The Örebro prevention programme as currently delivered in Sweden does not appear to reduce or delay youth drunkenness.
Trial registration: ClinicalTrials.gov NCT01213108.
© 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.