Effectiveness of a Global Mental Health Programme on Promoting Mental Health Characteristics Among Adolescents in Coimbatore, India: A Quasi-Experimental Study

Mental health of adolescents is a major global public health priority with about one in seven adolescents suffering from mental disorders. Despite India’s adolescent population being the world’s largest, there is a dearth of rigorously evaluated and culturally adapted school-based mental health programmes. A quasi-experimental time series design (O₁→X→O₂→O₃→O₄) was used to recruit 200 adolescents of 12–16 years of age through probability stratified random sampling from a higher secondary school. Mental health characteristics were assessed using a validated 80-item Mental Health Status Scale, which included five domains physical, intellectual, psychological, familial, and social. Data were analyzed using repeated measures ANOVA, MANOVA and one way ANOVA. Trial was registered with Clinical Trials Registry of India (CTRI/2026/04/107261). Baseline results showed that mental health characteristics were mostly poor, with 100% of the participants scoring poorly in the intellectual domain. "Post-intervention, participants reported a statistically significant, very large increase in overall mental health scores (mean gain = 18.53, 95% CI: 17.98–19.08; F(1,199) = 3872.54, p < 0.001, Cohen's d = 6.28) and showed statistically significant improvement across all five domains (p < 0.001). However, the social domain had the lowest mean post-test score (M = 4.77). Female adolescents and adolescents aged 14–15 years improved significantly more than their male counterparts (p < 0.001 for both). The findings provide evidence for the effectiveness of a school-based life skills programme for improving multiple dimensions of adolescent mental health and support its integration into school curricula in India as a scalable and cost-effective strategy.