Table 1.

Dataset characteristics.

	VinDr-CXR	ChestX-ray14	CheXpert	MIMIC-CXR	PadChest
Number of radiographs total (training set/test set) [n]	18,000 (15,000/3000)	112,120 (86,524/25,596)	157,878 (128,356/29,320)	213,921 (170,153/43,768	110,525 (88,480/22,045)
Number of patients (Total) [n]	N/A	30,805	65,240	65,379	67,213
Patient age [years]
Median	42	49	61	N/A	63
Mean ± Standard deviation	54 ± 18	47 ± 17	60 ± 18	N/A	59 ± 20
Range (minimum, maximum)	(2, 91)	(1, 96)	(18, 91)	N/A	(1, 105)
Patient sex female/male [%]
Training set	47.8/52.2	42.4/57.6	41.4/58.6	N/A	50.0/50.0
Test set	44.1/55.9	41.9/58.1	39.0/61.0	N/A	48.2/51.8
Projections [%]
Anteroposterior	0.0	40.0	84.5	58.2	17.1
Posteroanterior	100.0	60.0	15.5	41.8	82.9
Country	Vietnam	USA	USA	USA	Spain
Contributing hospitals [n]	2	1	1	1	1
Clinical setting	N/A	N/A	Inpatient and Outpatien t	Intensive Care Unit	N/A
Radiography systems [n]	≥ 8	N/A	N/A	N/A	N/A
Labeling method	Manual	Automatic (NLP)	Automatic (NLP)	Automatic (NLP)	Partially manual, Partially Automatic (NLP)
Radiographs with cardiomegaly [%]	11.8	2.5	12.6	19.7	8.9
Radiographs with Pleural effusion [%]	4.1	11.9	41.3	22.6	6.3
Radiographs with pneumonia [%]	4.0	1.3	2.5	6.5	4.7
Radiographs with atelectasis [%]	0.8	10.3	16.7	19.9	5.6
Radiographs with consolidation [%]	1.2	4.2	6.0	4.0	1.5
Radiographs with pneumothorax [%]	0.4	4.7	10.3	4.6	0.4
Radiographs without abnormality [%]	70.3	53.8	10.8	37.7	32.9

Indicated are the included datasets, i.e., VinDr-CXR²⁸, ChestX-ray14²⁹, CheXpert³⁰, MIMIC-CXR³¹, and PadChest³², and their characteristics. Only frontal chest radiographs (both anteroposterior and posteroanterior projections) were used for this study, while lateral projections were disregarded. Multiple radiographs may have been included per patient. N/A not available, NLP natural language processing.