Abstract
BACKGROUND: A growing body of evidence demonstrates that school-based mental health interventions may be potentially harmful. We define potential harm as any negative outcome or adverse event that could plausibly be linked to an intervention. In this scoping review, we examine three areas: the types of potential harms and adverse events reported in school-based mental health interventions; the subgroups of children and adolescents at heightened risk; and the proposed explanations for these potential harms. METHODS: We searched eight databases (1960-2023), performed an author search and hand-searched for published and unpublished studies that evaluated controlled trials of school-based group mental health interventions based on cognitive-behavioural therapy and/or mindfulness techniques, with the aim of reducing or preventing internalising symptoms or increasing wellbeing. Two independent raters screened studies for eligibility and assessed study quality using Cochrane tools. From eligible studies, we reviewed those that reported at least one negative outcome. RESULTS: Ten out of 112 (8.93%) interventions (described in 120 studies) reported at least one negative outcome such as a decrease in wellbeing or an increase in depression or anxiety. Three out of 112 interventions (2.68%) reported the occurrence of specific adverse events, none of which were linked to the intervention. Of the 15/120 studies rated as high quality (i.e. those with low risk of bias), 5/15 (33.33%) reported at least one negative outcome. Negative outcomes were found for a number of subgroups including individuals deemed at high risk of mental health problems, male participants, younger children and children eligible for free school meals. About half (54.5%) of the studies acknowledged that the content of the intervention itself might have led to the negative outcome. CONCLUSION: To design and implement effective school-based mental health interventions, the issues of potential harm and their related measurement and reporting challenges must be addressed.