Effectiveness of a universal, school-based, online programme for the prevention of anxiety, depression, and substance misuse among adolescents in Australia: 72-month outcomes from a cluster-randomised controlled trial
We found some evidence that a universal online programme for the prevention of anxiety, depression, and substance use delivered in early adolescence is effective in reducing the use and harmful use of alcohol into early adulthood. However, confidence in these findings is reduced due to baseline differences, and we did not see a difference in the predicted probability of drinking between groups at 72-month follow-up. These findings suggest that a universal prevention programme in adolescence is not sufficient to have lasting effects on mental health and substance use disorders in the long term.