Table 2. Datasets used for phase II deep convolutional neural network training and validation.

Dataset	Development phase	Total number of radiographs used	Number with suspected TB (%)	Number without suspected TB (%)
NIH CXR	Training/validation	100,622	44,521 (44.2)+	56,101 (55.8)+
Montgomery County, USA	Testing	138	58 (42.0)	80 (58.0)
Shenzhen, China	Testing	662	336 (50.8)	326 (49.2)
Johns Hopkins Hospital, Baltimore, MD, USA	Testing	100	35 (35.0)	65 (65.0)

+, ground truth determined by phase I deep learning system (DLS). CXR, chest radiograph; TB, tuberculosis.