Table 1.

The mean and standard deviation of the Euclidean distances between different sets of landmarks. All values have units of mm.

Landmark	Intra-Observer	Inter-Observer	Manual vs. Image	Manual vs. NICP
en_r	1.1 (0.7)	1.6 (1.0)	3.4 (2.6)	3.2 (1.9)
en_l	1.1 (0.8)	1.4 (0.9)	2.9 (2.0)	4.0 (1.7)
ex_r	0.9 (0.7)	1.2 (0.7)	2.5 (2.0)	2.5 (1.4)
ex_l	0.9 (0.7)	1.2 (0.8)	2.0 (1.7)	4.1 (1.6)
n	1.2 (0.9)	1.5 (0.9)	3.1 (2.4)	4.0 (1.7)
prn	0.9 (0.5)	1.1 (0.6)	1.9 (1.6)	2.7 (1.3)
sn	1.4 (0.8)	1.9 (1.2)	2.4 (1.6)	2.7 (1.1)
gn	1.1 (0.6)	1.8 (1.0)	2.9 (2.3)	3.3 (1.5)
ch_r	1.3 (0.8)	1.9 (1.3)	2.2 (1.6)	1.6 (1.0)
ch_l	1.0 (0.5)	1.4 (0.7)	2.0 (1.6)	3.0 (1.3)
ls	1.4 (0.9)	2.0 (1.3)	2.5 (1.7)	3.0 (1.3)
li	0.9 (0.6)	1.4 (0.8)	2.1 (2.1)	3.5 (1.5)
Overall	1.1 (0.8)	1.5 (1.0)	2.5 (2.0)	3.1 (1.6)