Stratified-Care School-Based Intervention for Adolescent Suicidal Ideation

Inclusion Criteria: * Inclusion Criteria for Educational Institutions * Located in Santiago, Chile. * Secondary education level (grades I-IV Medio). * Coeducational schools. * At least two classes per grade level in secondary education. * A minimum of 30 students per class. * Socioeconomic vulnerability level of ≥ 50%, as measured by the School Vulnerability Index (Índice de Vulnerabilidad Escolar - IVE-SINAE), which includes factors such as parental education and total household income. Inclusion Criteria for Students * Enrolled in grades I, II, or III Medio. * Suicidal ideation within the past month, defined as a score ≥ 3 on the Columbia-Suicide Severity Rating Scale (C-SSRS). * For the Reframe-IT+ program: mild or moderate depressive symptoms, defined as a PHQ-9 score \< 20. * For the CARIBOU program: severe depressive symptoms, defined as a PHQ-9 score ≥ 20. Exclusion Criteria: * Exclusion Criteria for Students * Participation in a structured suicide prevention program (Reframe-IT+) during 2024. * Severe psychotic symptoms, such as perceptual disturbances or delusional ideas, assessed during the eligibility interview. * Suicide attempt(s) in the past three months, assessed during the eligibility interview.