The effect of a universal, school-based social and emotional learning intervention (passport: Skills for life) on internalizing symptoms and related outcomes during the transition from childhood to adolescence: A cluster-randomized controlled trial.

Internalizing mental health difficulties impair quality of life, and their prevalence increases significantly during the transition from childhood to adolescence. This parallel cluster randomized controlled trial examined whether a universal, school-based social and emotional learning intervention (Passport: Skills for Life) could reduce internalizing symptoms and related outcomes compared with the usual school curriculum. Passport is implemented by trained classroom teachers, who deliver 18 weekly lessons across five modules (e.g., emotions; change and loss). Mainstream primary schools were the unit of randomization. A total of k = 62 schools (N = 2,425 children, aged 8–9 years) were randomly allocated to intervention (Passport; k = 33; n = 1,264) or control (k = 29; n = 1,161) conditions. The trial’s lead data analyst was masked to school allocation, but trial participants, schools, and the remaining authors were not. The intention-to-treat analysis of the primary outcome revealed no statistically significant impact of Passport on internalizing symptoms (d = −0.04, 95% bootstrapped confidence interval [BCI] = [−0.23, 0.15]). Secondary outcome analyses similarly revealed no statistically significant impact of the program (emotion regulation, d = 0.06, 95% BCI = [−0.13, 0.23]; well-being, d = −0.01, 95% BCI = [−0.18, 0.17]; loneliness, d = 0.02, 95% BCI = [−0.17, 0.20]; bullying, d = −0.07, 95% BCI = [−0.26, 0.11]; peer support d = −0.02, 95% BCI = [−0.19, 0.16]). Possible explanations for these null findings (e.g., program differentiation failure) are discussed, directions for future research are proposed, and implications for theory and practice are signposted.