Table 1:

Volume (milliliters) of whole brain and brain lobes in 52 control subjects, measured at baseline and again at 12 weeks postbaseline*

Structure	Baseline		Week 12		Mean Volume Difference		Percent Difference	Pearson Correlation	Concord
Structure	Mean	SD	Mean	SD	Mean	SD	Mean	Pearson Correlation	Concord
Whole brain	1190.4	127.0	1192.6	126.9	2.2	25.2	0.22	0.98	0.98
L frontal GM	157.2	16.8	158.6	14.8	1.4	4.7	1.08	0.96	0.95
R frontal GM	160.5	17.7	161.3	16.5	0.8	4.1	0.65	0.97	0.97
L occipital GM	59.3	6.9	59.1	6.4	−0.2	2.1	−0.20	0.95	0.95
R occipital GM	59.4	6.8	59.4	6.3	0.0	2.2	0.11	0.95	0.95
L parietal GM	62.7	7.1	62.4	6.8	−0.3	2.0	−0.34	0.96	0.96
R parietal GM	63.7	7.4	63.6	7.0	−0.1	2.5	−0.01	0.94	0.94
L temporal GM	67.8	8.1	68.0	7.4	0.2	3.0	0.59	0.93	0.92
R temporal GM	68.6	8.7	68.8	7.5	0.2	3.3	0.72	0.93	0.91
L frontal WM	141.9	14.5	142.4	13.4	0.6	5.3	0.58	0.93	0.93
R frontal WM	142.1	16.0	142.3	14.6	0.2	5.3	0.37	0.94	0.94
L occipital WM	17.1	2.9	16.9	2.9	−0.2	1.4	−0.64	0.89	0.88
R occipital WM	17.5	2.6	17.3	2.5	−0.2	1.3	−0.77	0.88	0.88
L parietal WM	46.1	5.7	45.6	5.6	−0.4	1.7	−0.87	0.96	0.95
R parietal WM	46.0	5.0	45.6	4.8	−0.3	1.8	−0.62	0.93	0.93
L temporal WM	36.0	4.9	36.0	4.1	0.0	2.1	0.55	0.90	0.89
R temporal WM	36.1	5.1	36.1	4.3	0.1	2.1	0.71	0.91	0.90
L caudate	4.3	0.6	4.3	0.6	0.0	0.5	1.46	0.58	0.58
R caudate	4.8	0.7	4.7	0.7	0.0	0.6	−0.21	0.57	0.56

Note:—Concord indicates concordance; L, left; R, right; GM, gray matter; WM, white matter.
* None of the mean volume differences were significant by paired-sample t test, and the Pearson correlation between week 0 and week 12 was generally quite high. Concordance is also a measure of the degree to which values at week 0 and week 12 are correlated, unlike the Pearson, which does not take account of the sample mean, concordance is sensitive to changes in sample mean.