Stratified-Care School-Based Intervention for Adolescent Suicidal Ideation

Background. Suicidal ideation and depressive symptoms are highly prevalent among adolescents, with suicide representing a leading cause of death in this age group worldwide. School-based indicated prevention programs using cognitive behavioral therapy (CBT) have shown promise in addressing these mental health challenges. The Reframe-IT+ (Chile) and CARIBOU (Canada) programs are CBT-based, individually delivered interventions targeting adolescents at risk of suicide. This study aims to evaluate a culturally adapted stratified-care model using these two interventions, matched to depressive symptom severity. Methods. This is a quasi-experimental, single-arm study with pre-post assessments and follow-ups at 3, 6, 9, and 12 months. Six secondary schools with high socioeconomic vulnerability in Santiago, Chile, will participate. Students with suicidal ideation and mild/moderate depressive symptoms (PHQ-9 \< 20) will be offered Reframe-IT+, while those with severe symptoms (PHQ-9 ≥ 20) will be offered CARIBOU. Primary outcomes include the acceptability of CARIBOU, feasibility of the stratified-care model, and implementation fidelity. Secondary outcomes include reductions in suicidal ideation, depression, anxiety, hopelessness, and improvements in functioning, quality of life, behavioral activation, emotional regulation, and problem-solving skills. Discussion. This protocol addresses the need for scalable, culturally sensitive interventions for adolescent suicide prevention in school settings. By evaluating both the process and early outcomes of a stratified-care approach, this study will generate valuable evidence to inform future large-scale effectiveness trials and policy development in adolescent mental health.