Table 1.

Characteristics of patients and lesions in test image sets

Characteristics	WCH data set (n = 1,239)		External test data set (n = 96)
	Training (n = 977)	Internal test data set(n = 262)
Patient characteristics
Age, yr	61 (36–84)	63 (39–82)	65 (40–85)
Sex
Male	649	186	62
Female	328	76	34
Lesion characteristics
Size (mm), mean (range)	29 (5–88)	27 (5–85)	26 (5–70)
Location (Ut/Mt/Lt)	142/572/263	55/167/40	26/49/21
Macroscopic type (IIa/IIb/IIc/IIa + IIc)	15/557/368/37	4/177/53/28	0/59/32/5
Invasion depth (EP-LPM/MM/SM/uncertain)	483/235/222/37	146/67/40/9	51/32/8/5

Values are median (range).

EP-LPM, epithelium-lamina propria; Lt, lower esophagus; MM, muscularis mucosa; Mt, middle esophagus; SM, submucosa; Ut, upper esophagus; WCH, West China Hospital.