Table 3.

Interoperator Error (Mutual-Difference in Pixels) on First and Second Testing Data Sets^a

Interface	Error on Averaged Images			Error on Raw Images			Mean Error Over All Images
	First vs. Second Operators	Third vs. Fourth Operators	Meanb	First vs. Second Operators	Third vs. Fourth Operators	Meanb
EP	2.12 ± 1.65	1.39 ± 1.10	1.79 ± 1.47*	2.15 ± 1.76	1.81 ± 1.63	1.99 ± 1.71	1.89 ± 1.60
BS	3.99 ± 2.47	2.02 ± 1.55	3.09 ± 2.32*	3.53 ± 2.53	1.84 ± 1.65	2.78 ± 2.34	2.94 ± 2.34
BW	2.61 ± 2.17	1.33 ± 1.15	2.03 ± 1.89*	3.00 ± 2.88	1.45 ± 1.19	2.31 ± 2.42	2.17 ± 2.17
ST	3.43 ± 3.06	1.70 ± 1.48	2.66 ± 2.63*	3.98 ± 3.88	1.98 ± 1.73	3.22 ± 3.38	2.93 ± 3.02
DM	7.54 ± 4.13	2.25 ± 1.85	5.43 ± 4.28**	7.43 ± 6.03	2.53 ± 1.88	5.62 ± 5.46	5.52 ± 4.89
EN	3.38 ± 4.06	2.01 ± 1.90	2.81 ± 3.41*	4.41 ± 6.70	1.98 ± 1.58	3.48 ± 5.48	3.13 ± 4.54
Mean	3.84 ± 3.54	1.76 ± 1.55	2.93 ± 3.02*	4.08 ± 4.66	1.90 ± 1.64	3.17 ± 3.87	3.05 ± 3.47

^aFirst and second operators segmented the first testing data set, and the third and fourth operators segmented the second testing data set.

^b*P < 0.0001, **P = 0.0528 (significance level = 0.05).