Validation and Psychometric Properties of a Depression Scale for People with Tuberculosis in Lima, Peru

Background Depression is a known risk factor for poor outcomes during tuberculosis (TB) treatment. Assessing depressive symptoms in TB patients is challenging due to overlap with symptoms of the disease and side effects of treatment, such as fatigue, sleep disturbance, and appetite changes. This study aimed to develop and validate a screening scale for major depressive episodes in patients undergoing TB treatment. Methods A cross-sectional validation study was conducted using 58 items drawn from previously validated Spanish-language depression scales. These items were administered to adults receiving TB treatment in Lima, Peru. Diagnosis of a major depressive episode was determined through a SCID-5 interview conducted by a psychiatrist. Items were selected sequentially based on individual area under the receiver operating characteristic curve (auROC), with the final selection made when no further gain in discrimination was observed. Internal consistency and diagnostic performance were assessed. Results Among 163 participants, an 8-item scale achieved an auROC of 95.9% (95% CI: 92– 99.9%), sensitivity of 87.2%, and specificity of 92.2% at a cutoff score ≥11. Internal consistency was good (Cronbach’s α and McDonald’s ω = 0.804). Items on anhedonia, energy, sleep, and appetite were excluded. Conclusion The validated 8-item scale showed strong discriminative accuracy and internal consistency for detecting major depressive episodes in TB patients.