Individual‐, family‐, and school‐level interventions targeting multiple risk behaviours in young people.

Our findings suggest that school‐based interventions offered to all children that aim to address engagement in multiple risk behaviours may have a role to play in preventing tobacco use, alcohol use, illicit drug use, and antisocial behaviour, as well as in improving physical activity, among young people, but not in the other behaviours examined. We did not find strong evidence of benefit of interventions for families or individuals. Concerns around reporting of studies and study quality highlight the need for additional robust, high‐quality studies to further strengthen the evidence base in this field