Table 1.

Distribution of class instances and datasets.

	Train	Validation	Internal test	Total	External test
Class instances
Gangrene	374 (27.7%)	108 (27.8%)	61 (29.7%)	543	100 (17%)
Normal	302 (22.4%)	89 (22.9%)	49 (23.9%)	440	0 (0%)
Ulcer	344 (25.5%)	97 (25%)	48 (23.4%)	489	346 (57%)
Infection	332 (24.5%)	94 (24.2%)	46 (22.9%)	472	149 (26%)
Datasets
DFUC 2020	422 (31.2%)	119 (30.7%)	62 (30.4%)	603	–
Xiangya hospital	594 (43.9%)	164 (42.3%)	65 (31.9%)	823	–
Kaggle	336 (24.9%)	105 (27.1%)	77 (37.7%)	518	–
Total	1352 (70%)	388 (20%)	204 (10%)	1944	595