Figure 4. Distribution of published studies on clinical algorithms for diagnosing smear-negative TB in patients presenting with symptoms (“rule-in”), by geography, objective, and study setting.

Effectiveness studies, algorithm relate to studies designed to evaluate predefined clinical algorithms, and effectiveness studies, diagnostics to studies designed to evaluate combined diagnostic methods, both for diagnosing smear-negative TB among TB suspects done in routine or mixed routine-research settings. Delivery relates to studies designed to address diagnostic practices and improvement of smear examination or sputum collection to improve diagnosis of smear-negative TB. One study evaluated both combined diagnostic methods and a predefined clinical algorithm. Two cost-effectiveness studies were also included as evaluations of combined diagnostic methods.