How to measure children’s feet: 3D foot scanning compared with established 2D manual or digital methods

Table 4 Indicators^a of bias and heteroscedasticity for comparison of manual, 2D and 3D measurements for parameters of foot length, width and breadth

(A) Manual foot measurement (MF) vs. 2D Foot Scan (2D)
outcome	MF [mm]	2D [mm]	Pearson R	Bias	Upper LoA	Lower LoA
outcome	MF [mm]	2D [mm]		[mm]	[mm]	[mm]
Foot length, FL	201.4 ± 18.0	197.5 ± 17.4	0.14	0.40	1.33	-0.54
Projected foot width, FW_P	74.9 ± 6.0	76.3 ± 6.8	-0.05	-0.13	0.39	-0.66
(B) Manual foot measurement (MF) vs. 3D Foot Scan (3D)
outcome	MF [mm]	3D [mm]	Pearson R	Bias	Upper LoA	Lower LoA
outcome	MF [mm]	3D [mm]		[mm]	[mm]	[mm]
Foot length, FL	201.4 ± 18.0	203.7 ± 18.1	-0.02	-0.23	0.26	-0.72
Anatomical foot ball breadth, FB	200.2 ± 17.5	197.0 ± 16.6	0.11	0.32	2.01	-1.38
(C) 2D vs. 3D Foot Scan (3D)
outcome	2D	3D	Pearson R	Bias	Upper LoA	Lower LoA
outcome	2D	3D		[mm]	[mm]	[mm]
Foot length, FL	197.5 ± 17.4	203.7 ± 18.1	-0.14	-0.63	0.34	-1.59
Anatomic foot width, FW_A	78.0 ± 6.8	80.7 ± 6.9	-0.06	-0.27	0.10	-0.64

ISSN: 1757-1146