Figure 1From: How much is tuberculosis screening worth? Estimating the value of active case finding for tuberculosis in South Africa, China, and India Schematic of compartmental TB transmission model. Boxes represent states in the model (HIV not shown but a more complete diagram can be found in Additional file 1: Figure S1) and arrows represent flows between the states. We model active TB case finding as a one-time increase in the rate of “Detection and Diagnosis,” which incorporates all efforts from screening to initiation of therapy but does not detect pre-symptomatic cases.Back to article page