Abstract

Background: Suicide is the leading cause of death among young people. Because it is preventable, suicide prevention has become a critical public health priority worldwide. Current evidence suggests that primary suicide prevention interventions are effective in promoting suicide awareness and reducing suicidal thoughts among adolescents. However, scarce research has been conducted in vulnerable populations who may be at increased risk of suicidal behaviour. This project aims to test the effectiveness of a primary suicide prevention intervention on suicide awareness, knowledge of suicide and local resources, suicidal thoughts, psychological distress, and safety. Methods: This study is an open-label, multi-centre, superiority, cluster-randomized controlled trial with two parallel arms (randomization 1:1 in at least 8 study sites) of a primary suicide prevention intervention based on psychoeducation versus an art-based control intervention. Four groups of youth aged 14–25 with high suicide risk will be recruited (in total, n = 240), including those (1) detained in juvenile detention centres, (2) disconnected from school, (3) in treatment for psychiatric disorders, (4) belonging to a sexual or gender diversity, (5) affected by chronic conditions, and (6) with relational/familial problems. Participants will be randomly assigned to the suicide prevention or control intervention. The primary outcome is suicide awareness measured on a validated scale. Secondary outcomes include knowledge of suicide, knowledge of local resources, suicidal behaviour, psychological distress, access to primary suicide prevention, and safety. Measures will be collected at baseline, at 1-week, and 3-month follow-ups. Analyses will be conducted as intention-to-treat using mixed-effects models. Discussion: We expect that a brief primary suicide prevention intervention (psychoeducation) will be effective and safe in vulnerable adolescents. Trial registration: ClinicalTrials.gov NCT06551038. Registered on August 13, 2024. © The Author(s) 2025.