Stress in Study: Assessing Depression Differences Among Medical and Non- Medical Students

Background University students experience significant academic stress, which may contribute to depressive symptoms. Evidence comparing depression levels between medical and non-medical students in South Asia remains limited. This study examined differences in depressive symptoms and assessed the psychometric properties of the PHQ-9 and DASS-21 scales in a large student sample. Methods A cross-sectional survey was conducted among 602 students (Medical: n = 424; Non-Medical: n = 178) using the Patient Health Questionnaire-9 (PHQ-9) and the Depression, Anxiety, and Stress Scales-21 (DASS-21). Analyses included descriptive statistics, reliability (Cronbach’s α), confirmatory factor analysis (CFA), item response theory (IRT), and symptom network analysis, conducted in R. Results Median PHQ-9 scores were slightly higher among non-medical students (10.0, Q1–Q3 = 7.0–14.0) compared to medical students (9.0, Q1–Q3 = 5.0–13.0). Internal consistency was high for PHQ-9 (α = 0.82), DASS-Depression (α = 0.88), DASS-Anxiety (α = 0.85), and DASS-Stress (α = 0.86). CFA supported the three-factor DASS-21 model with good fit (CFI = 0.95, TLI = 0.95, RMSEA = 0.052, SRMR = 0.031). IRT analyses showed strongest discrimination for self-worth, concentration, down, and appetite items, while interest contributed the least. Symptom network analysis identified self-worth, concentration, and meaninglessness as central nodes, with somatic items (sleep, appetite, energy) bridging across domains. Conclusions Non-medical students reported slightly higher depressive symptoms compared to medical students, though both groups showed substantial burden. The PHQ-9 and DASS-21 demonstrated excellent reliability and construct validity. Interventions should target central symptoms, such as self-worth and concentration difficulties, to enhance mental health support in university populations.