Fig. 4: Performance of CAD4TB v5 and v6.

Receiver-operating curve of CAD4TBv5 (a) and v6 (b) triaging thresholds for each TB diagnostic group: definite TB (microbiologically confirmed, positive: n = 99, negative: n = 4877), definite TB, trace excluded (a more stringent group that excludes those whose only microbiological evidence of TB is an Xpert “trace” results, positive: n = 75, negative: 4901), and probable TB (radiologically diagnosed, positive: n = 172, negative: n = 9742). The radiologist’s sensitivity and specificity of detecting definite TB (+) and definite TB trace excluded (x) is marked. The (c) percentage of participants who would have required sputum testing at each CAD4TB triaging threshold (n = 9914) and (d) number of definite TB cases that would have been missed at each CAD4TB triaging threshold (n = 99). In (c) and (d) the horizontal dashed line indicates the radiologist’s performance and vertical lines indicate the CAD4TBv5 triaging thresholds used in the pilot (60) and main study phase (25).