Chest radiography for active tuberculosis case finding in the homeless: a systematic review and meta-analysis.

SETTING In low-incidence regions, tuberculosis (TB) often affects vulnerable populations. Guidelines recommend active case finding (ACF) in homeless populations, but there is no consensus on a preferred screening method. OBJECTIVE We performed a systematic review and meta-analysis to evaluate the use of chest X-ray (CXR) screening in ACF for TB in homeless populations. DESIGN Articles were identified through EMBASE, Medline and the Cochrane Library. Studies using symptom screens, CXRs, sputum sweeps, tuberculin skin tests and/or interferon-gamma release assays to detect active TB in homeless populations were sought. Data were extracted using a standardised method by two reviewers and validated with an objective tool. RESULTS Sixteen studies addressing CXR screening of homeless populations for active TB in low-incidence regions were analysed. The pooled prevalence of active TB in the 16 study cohorts was 931 per 100 000 population screened (95%CI 565-1534) and 782/100 000 CXR performed (95%CI 566-1079). Six of seven longitudinal screening programs reported a reduction in regional TB incidence after implementation of the CXR-based ACF programme. CONCLUSION Our data suggest that CXR screening is a good tool for ACF in homeless populations in low-incidence regions.