I guess the easiest way is to save the output cluster number (--ocn option to mri_surfcluster), then create a segmentation lookup table (like FreeSurferColorLUT.txt), one row for each of your clusters. Then run mri_segstats, passing the ocn as the --seg, your new color table as --ctab, the mri_glmfit --y input as --in, and use the --avgwf output of mri_segstats. The output in this case will be an average thickness (or whatever --y was) for each subject for each cluster. I have not tried this before, so let me know if this works.
doug
Don.Rojas@uchsc.edu wrote:
Hello all,
I have just completed a group analysis of cortical thickness, including running the full Monte Carlo simulation to obtain cluster-wise multiple comparison corrections. Now I would like to know, for the clusters I'm interested in, how best to go about doing a statistical power analysis for an upcoming grant application, based on the completed analysis. Is there some easy way to extract the thickness for all individual subjects for a specified cluster, either for all vertices within the cluster, for the mean of all vertices within the cluster, or even for the peak vertex (maximum group difference), so that I can compute group mean and standard deviations for a measure of effect size?
Thanks,
Don
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