Preventing Mental Disorders in Children: A Systematic Review to Inform Policy-Making

Background: At any given time, 14% of Canadian children experience clinically significant mental disorders, which frequently persist into adulthood. Canadian public policy has emphasized specialized treatment services, yet these services only reach 25% of children with disorders. Prevention programs hold potential to reduce the number of children with disorders in the population. To inform policy-making, we systematically reviewed the best available research evidence on programs for preventing conduct disorder (CD), anxiety and depression, three of the most prevalent mental disorders in children.
Methods: We systematically identified and reviewed randomized controlled trials (RCTs) on programs intended to prevent CD, anxiety and depression in children aged 0–18 years.
Results: Fifteen RCTs met selection criteria: nine (on eight programs) for preventing CD; one for anxiety; four (on three programs) for depression; and one for all three. Ten RCTs demonstrated significant reductions in child symptom and/or diagnostic measures at follow-up. The most noteworthy programs, for CD, targeted at-risk children in the early years using parent training (PT) or child social skills training (SST); for anxiety, employed universal cognitive-behavioural training (CBT) in school-age children; and for depression, targeted at-risk school-age children, also using CBT. Effect sizes for these noteworthy programs were modest but consequential. There were few Canadian studies and few that evaluated costs.
Discussion: Prevention programs are promising but replication RCTs are needed to determine effectiveness and cost-effectiveness in Canadian settings. Four program types should be priorities for replication: targeted PT and child SST for preventing CD in children’s early years; and universal and targeted CBT for preventing anxiety and depression in children’s school-age years. Conducting RCTs through research-policy partnerships would enable implementation in realistic settings while ensuring rigorous evaluation. Prevention merits new policy and research investments as part of a comprehensive public health strategy to improve children’s mental health in the population.