Methodologies for studying depression in persons with tuberculosis: A scoping review

Depression is prevalent among people with tuberculosis (PWTB) and negatively affects diagnosis, treatment adherence, and clinical outcomes. However, the methodological approaches used to study depression among PWTB have not been systematically mapped. This scoping review aimed to evaluate methodologies used to study depression among PWTB and identify gaps in methodological approaches. We conducted a systematic scoping review following PRISMA-ScR guidelines. Nine databases were searched without date restrictions. Two reviewers independently screened titles, abstracts, and full texts. Inclusion criteria included primary, peer-reviewed, research studies that examined depression among PWTB, and reported outcomes related to TB and depression. Data were extracted on study characteristics, TB population, depression measurement tools, treatment approaches, and implementation considerations. Findings were organized using Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework. A total of 184 studies met inclusion criteria. Research was dominated by cross-sectional designs (65%), with fewer cohort studies (17%) and only eight randomized controlled trials (RCTs, 4%). The RCTs primarily evaluated psychological interventions that demonstrated modest improvements in depressive symptoms or TB-related outcomes. Depression was overwhelmingly assessed using screening tools with only 28 studies (15%) using a diagnostic interview or clinical criteria. None evaluated accuracy of any screening or diagnostic tool. Studies were geographically clustered, with more than one-third conducted in India or China. Implementation barriers to integrated TB and depression care included workforce shortages and stigma; facilitators included task-shifting and embedding screening into routine workflows. No studies reported on maintenance or long-term sustainability of depression care within TB programs. Existing research on depression among PWTB is largely cross-sectional, relies heavily on screening tools, and rarely evaluates interventions or their sustainability. Expanding population and geographic coverage, incorporating longitudinal designs and diagnostic evaluation, and strengthening implementation and maintenance research are critical for developing sustainable, integrated approaches to depression care within TB services.