Figure 2.

Time to correct assignment of patients by the various screening packages. This graph represents the time until the 435 patients who provided two sputum samples would have been correctly assigned as TB-positive or TB-negative by the various screening packages. Each package is represented by a distinct line, with the maximum height on the y-axis signifying the number of patients correctly assigned by that package. A patient was considered “correctly assigned” if and when 1) any component of the screening package was positive and any microbiologic test result was positive or 2) all components of the screening package were negative and all microbiologic test results were negative. Patients who failed to complete all components of a package were considered “not correctly assigned,” unless at least one component test was positive in the context of a positive microbiologic test result. Packages delivering the best performance in correct patient assignment reach furthest up the y axis, whilst the speed with which results are available is reflected on the x axis. An ideal package would be represented by a straight vertical line which ended in the top left hand corner. Re-culturing times for contaminated samples are included. Exam=clinical exam by referring physician. CXR=chest radiograph. LJ=Lowenstein-Jensen.