Table 2.

Common mean volume of structures across both methods (in mL) for 69 pairs of volume estimates, along with per-subject differences from the common mean (in volume and percentage volume)

Region	Mean common volume	Mean volume difference	% volume difference	T-value	P-value	95% confidence interval
						ICC	Low	High
L cerebral cortex	246.1	63.9	26.0	15.6	<0.0001	0.50	0.30	0.66
R cerebral cortex	246.7	62.7	25.4	14.9	<0.0001	0.47	0.27	0.64
L cerebral white matter	215.0	16.3	7.6	6.4	<0.0001	0.81	0.71	0.88
R cerebral white matter	216.8	14.0	6.5	6.1	<0.0001	0.85	0.77	0.90
L Lat Vent	12.7	0.2	1.4	1.6	0.11	0.99	0.99	1.00
R Lat Vent	11.0	−0.1	−0.5	−0.5	0.61	0.99	0.98	0.99
L thalamus	6.3	0.7	11.2	10.5	<0.0001	0.77	0.66	0.85
R thalamus	6.4	0.8	12.0	12.0	<0.0001	0.75	0.63	0.84
L hippocampus	3.6	0.0	−0.2	−0.1	0.92	0.55	0.37	0.70
R hippocampus	3.8	0.0	−1.3	−0.9	0.37	0.61	0.43	0.74
L amygdala	1.6	0.0	−0.8	−0.4	0.67	0.57	0.38	0.71
R amygdala	1.6	−0.1	−6.2	−3.3	0.001	0.52	0.33	0.68
L caudate	3.4	−0.1	−1.7	−1.5	0.13	0.82	0.73	0.88
R caudate	3.5	0.1	2.2	1.8	0.07	0.79	0.68	0.86
L putamen	4.6	−0.2	−3.4	−2.2	0.029	0.56	0.38	0.70
R putamen	4.6	0.1	1.6	1.2	0.25	0.61	0.44	0.74
L pallidum	1.8	−0.3	−15.1	−8.0	<0.0001	0.52	0.32	0.67
R pallidum	1.7	−0.2	−10.9	−5.0	<0.0001	0.48	0.28	0.64
L accumbens area	0.53	0.1	17.1	4.6	<0.0001	0.26	0.03	0.47
R accumbens area	0.54	0.1	13.1	3.0	0.004	0.20	−0.04	0.41

Note: The test statistic is given for the hypothesis that the average volume difference is 0, as an indicator of difference in the measurement. Positive values indicate the CMA volume is greater than the FreeSurfer volume. The ICC is given for the assumption of the consistency of volumes between methods (see text for details).

Abbreviations: CMA, Center for Morphometric Analysis; ICC, intraclass correlation coefficient.