A Systematic Review of Intervention Studies on Adolescents with Depression and Anxiety in Low and Middle-Income Countries

Background and Purpose: One in 7 adolescents aged 10 to 19 worldwide suffer from mental disorders. Anxiety and depression disorders makeup about 40% of mental disorders Adolescents in low-and middle-income countries (LMICs) are particularly vulnerable due to limited access to evidence-supported mental health services. Evidence from LMICs, where 90% of the world’s adolescents live, remains scarce. In response to an international action plan to promote mental health by WHO (2013), a systematic review of intervention studies to reduce depression and anxiety in LMICs was conducted. This review addressed the following research questions: 1) What types of interventions were used to reduce depression and anxiety among adolescents in LMICs? 2) What was the methodological quality of these studies? 3)What types of interventions (school versus non-school-based) were most effective when considering the study’s methodological rigor?

Methods: A systematic search of five databases was conducted to identify publications. Studies were included if they were: 1) peer-reviewed publications between 2013- 2024, 2) written in English; 3) conducted in an LMIC; 4) quasi-experimental or experimental designs; 5) quantitative evaluations on depression and/or anxiety;6) participants ages 10-19 who screened positive for symptoms of depression Studies that only evaluated medical interventions were excluded. The 12-item Methodological Quality Rating Scale (MQRS) was used to assess methodological rigor. Strength of the evidence for each study was evaluated by combining methodological rigor with statistical significance on outcomes of depression and anxiety according to the following ratings: “strong” evidence (significant outcomes with high rigor); “promising” evidence (significant outcome with low rigor); or “weak” evidence (non-significant outcome with high or low rigor). The strength of evidence was compared by intervention setting (school vs non-school).

Results: Seventeen studies met inclusion criteria. Ten studies were school-based, and 7 were non-school-based. Analysis of MQRS showed that of a possible range of 0-13, the actual scores ranged from 6 to 13 with a median of 10 (Mean=9.65, SD=2.29). Using the median split, of the 17 studies, 7 had higher methodological rigor, and 10 had lower rigor. Non-school based studies were of lower rigor than school-based. Strengths across interventions were theory-informed interventions, dosage, and reliable measures. The weaknesses were statistical power, follow-up, and multisite designs. Eight studies included depression; 5 were school-based, and 3 non-school-based studies. Four of 5 school-based studies showed significant outcomes. One of 3 non-school-based studies was significant. Eleven studies included anxiety; 8 were school-based, and 3 were non-school-based. Seven of 8 school-based studies showed significant results, most with higher rigor, and 3 of 3 non-school-based were significant, but all had lower rigor.

Conclusions and Implications: These findings suggest that school-based interventions have slightly stronger evidence for reducing depression than non-school based, and they were of higher rigor. More research is needed to improve the rigor of non-school based studies with more statistical power, multi-sites, and longer follow-ups. Also, future research may be warranted to compare the cost-effectiveness of school versus non-school interventions in LMICs where mental health resources are limited.