Table 2.

Scoring system to evaluate the accuracy of the automated camera system.

Parameter	Scoring level	Definition
Metatarsal footpad	0	Detection is correct (including the gap/interspace between metatarsal footpad and toes)
	1	Detected area is bigger than the “true” metatarsal footpad or slipped out of position; <1/2 segment of a toe
	2	Detected area is bigger than the “true” metatarsal footpad or slipped out of position; >1/2 segment of a toe
	3	Detected area is smaller than the “true” metatarsal footpad
Alteration	0	Detection is correct
	1	Detected area is bigger than the “true” alteration
	3	Detected area is smaller than the “true” alteration
Angle of presentation	0	Aligned straight to the camera
	1	Aligned slightly skew
	2	Aligned skew

“True” metatarsal footpad refers to the definition of metatarsal footpad by the automated camera system (i.e., cutting the toes off and putting a circle around the rest; see Material and Methods for detailed description), which does not take the three-dimensional appearance of the metatarsal footpad into account. Automated detection of the metatarsal footpad is marked in green; automated detection of the alteration is marked in red; pictures by Jenny Stracke.