Schools can be pivotal in addressing mental health challenges, especially in low-income settings like Uganda. This pilot cluster-randomized trial examines the impact of a culturally sensitive Act-Belong-Commit (ACT) intervention, combined with physical activity, sleep hygiene and stress management measures on anxiety and depression among Ugandan adolescents attending secondary school. Adolescents from four secondary schools were randomized by school to either a 12-week, weekly two-hour teacher- and peer-led ACT intervention or a care-as-usual control. Anxiety (GAD-7) and depression (PHQ-9-A) were measured at baseline and immediately post-intervention. Childhood trauma (CTQ-SF), self-reported health, wealth, and food security were assessed at baseline. Linear mixed modeling was used to evaluate intervention effects.

Introduction: Schools can be pivotal in addressing mental health challenges, especially in low-income settings like Uganda. However, randomized controlled trials tailored to cultural and contextual factors are scarce. This pilot cluster-randomized trial examines the impact of a culturally sensitive Act-Belong-Commit (ACT) intervention, combined with physical activity, sleep hygiene and stress management measures on anxiety and depression among Ugandan adolescents attending secondary school.

Methods: A total of 2,598 adolescents (1,295 intervention; 1,303 control; 1,199 boys [46.1%]; mean age 16.3 ± 1.0 years) from four secondary schools were randomized by school to either a 12-week, weekly two-hour teacher- and peer-led ACT intervention or a care-as-usual control. Anxiety (GAD-7) and depression (PHQ-9-A) were measured at baseline and immediately post-intervention. Childhood trauma (CTQ-SF), self-reported health, wealth, and food security were assessed at baseline. Linear mixed modeling was used to evaluate intervention effects.

Inclusion Criteria:

• All students aged 14 to 17 years in the four schools were screened for depression and anxiety using the Patient Health Questionnaire - 9 (PHQ-9) (Spitzer et al., 1999) and Generalized Anxiety Disorder - 7 (GAD-7) (Spitzer et al., 2006) as part of school health screening service embedded within the study.

Exclusion Criteria:

• None

Masked for group allocation