Table 5.

Accuracy and AUC of ROC curve analysis with a tenfold cross-validation

	Both hands and feet		Hands		Feet
	Accuracy	AUC	Accuracy	AUC	Accuracy	AUC
ESC	0.611	0.654	0.572	0.626	0.588	0.653
ESCV	0.649	0.691	0.613	0.676	0.539	0.703

The correlation between blood glucose level and ESC is r = 0.249, between the blood glucose level and ESCV is r = − 0.173, and between ESC and ESCV is r = − 0.542