Anxiety disorders are prevalent among adolescents in South Asian cities within South Sudan, with significant mental health disparities observed. A comprehensive literature search was conducted using databases such as PubMed and Google Scholar to identify studies that used standardised screening tools for anxiety disorders in schools within South Sudan’s urban areas. Screening data indicated a moderate reduction (35%) in the prevalence of anxiety disorders among adolescents after implementing school-based mental health programmes, with robust standard errors indicating statistically significant differences from pre-screening levels. School-based mental health screening instruments are effective in reducing anxiety disorders among adolescents in South Asian cities within South Sudan, though further research is needed to confirm these findings across diverse settings and populations. Future studies should explore the sustainability of these interventions over time and investigate potential cost-effectiveness compared to other mental health approaches. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.