Relational Well-Being and Adolescent Depression: Evidence from Secondary Schools in Dodoma and Pwani, Tanzania

Adolescent depression is a growing public health concern in Tanzania, yet existing research has emphasised structural risk factors such as poverty and HIV status, with limited attention to relational determinants. Guided by Relational Well-Being Theory, this study examined associations among family dynamics, peer relations, life satisfaction, perceived social support, and depressive symptoms among secondary-school adolescents in the Dodoma and Pwani regions. A cross-sectional survey design was used, involving 1,009 adolescents aged 11–19 years. Standardised instruments were administered via KoboToolbox, and data were analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM). The structural model explained 47.9% of the variance in depressive symptoms (R² = 0.479). Family dynamics (β = 0.449, p < 0.001, f² = 0.363) and peer relations (β = 0.423, p < 0.001, f² = 0.320) were strongly and statistically significantly associated with depressive symptoms. In contrast, life satisfaction (β = 0.024, p = 0.384) and perceived social support (β = −0.015, p = 0.653) were not significantly associated within the model. The findings highlight the salience of proximal relational environments for adolescent mental health in Tanzania. Interventions focusing on family cohesion and positive peer engagement may warrant consideration in efforts to address depressive symptoms in secondary schools.