Table 3.

Overview of differentiating characteristics of two features

Feature	Sensitivity	Specificity	Correlation with clinical scale
Mean of grey values t = 30 to t = 0	100	72	0.34
Gradient of detected wrinkle t = 15 to t = 0	67	97	0.50
Gradient of detected wrinkle t = 30 to t = 0	83	76	0.77

Clinical scores on the finger wrinkling test were used as a gold standard