Table 4. Power analysis for signal change over sensorimotor cortex.

Groups (controls/patients)	Region	Controls		Schizophrenics		Signal diff.	Power	Req'd signal diff. for P>0.8
		PS	STD	PS	STD
Site-A (16/16)	Left	0.615	0.376	0.770	0.494	0.155	0.162	0.451
	Right	0.173	0.304	0.429	0.414	0.256	0.486	0.373
	Both	0.480	0.286	0.636	0.407	0.157	0.229	0.362
Site-C (11/10)	Left	1.238	0.581	1.231	0.530	-0.008	0.050	0.716
	Right	0.353	0.361	0.332	0.566	-0.021	0.051	0.628
	Both	0.948	0.476	0.935	0.488	-0.012	0.050	0.644
Site-E (13/14)	Left	0.613	0.424	0.613	0.320	0.000	0.050	0.426
	Right	0.311	0.431	0.406	0.504	0.095	0.080	0.525
	Both	0.497	0.413	0.517	0.328	0.020	0.052	0.422
Site-G (14/12)	Left	0.850	0.255	0.869	0.295	0.018	0.053	0.320
	Right	0.435	0.421	0.229	0.189	-0.207	0.349	0.370
	Both	0.688	0.328	0.622	0.242	-0.066	0.087	0.328
Site-H (17/14)	Left	0.738	0.122	0.858	0.416	0.120	0.164	0.345
	Right	0.248	0.435	0.310	0.345	0.062	0.071	0.406
	Both	0.544	0.371	0.665	0.331	0.121	0.153	0.366
All sites (71/66)	Left	0.787	0.502	0.837	0.444	0.050	0.094	0.228
	Right	0.296	0.335	0.348	0.409	0.052	0.127	0.181
	Both	0.612	0.396	0.656	0.372	0.044	0.102	0.185

The five sites with at least 10 subjects per diagnostic group were included in the power analysis of the percent signal change (PS). The mean PS and standard deviation (STD) is shown for the left sensorimotor cortex, right, and combined, per site, and over all sites. The final column is the signal difference which that sample had the power to detect. The number of subjects actually collected from each site is listed below the site code.