Short Video-Based Mental Health Intervention for Depressive Symptoms in Junior High School Students: A Cluster Randomized Controlled Trial

PURPOSE: Digital interventions for adolescent mental health are emerging in high-income countries, but have faced challenges and are scarce in China. This study investigated the effect of a short video-based mental health intervention on depressive symptoms in Chinese adolescents. METHODS: A three-arm cluster randomized controlled trial was conducted in four junior high schools in Shanghai from December 2020 to December 2021 with the measurement at baseline, 6 months after study entry, and 12 months. Outcomes were collected by self-completed questionnaires administered by teachers masked to allocation. The primary outcome was depressive symptoms assessed by the Depression Self-Rating Scale for Children (DSRSC). Mixed effects models were used to compare psychologist-led intervention (n=428 students) and teacher-led intervention (n=385) including six short video-based sessions to usual school provision (n=751). RESULTS: Using intention-to-treat analyses, psychologist-led intervention showed more reduction in depressive symptoms compared to usual school provision at 6 months (coefficient −1.00, 95% CI −1.94 to −0.05), but not at 12 months. Using per-protocol analyses among participants who watched at least three video episodes, both psychologist-led (−1.14, −2.20 to −0.09) and teacher-led intervention (−1.23, −2.45 to −0.02) reduced depressive symptoms compared to usual school provision at 6 months, and the effect of teacher-led intervention persisted at 12 months (−1.58, −3.13 to −0.03). Further exploration found that compared with urban students, the between-group differences for depressive symptoms in rural students were more significant (p<0.05 for interaction) and the effects were maintained at 12 months. CONCLUSION: The short video-based mental health intervention showed potential to reduce depressive symptoms among Chinese adolescents, and the effects were more significant if the minimum video viewing frequency was reached.