Hello everyone,
I'm working on the preprocessing of VBM analysis. After running the
"Check Sample Homogeneity Using Covariance", I face some problems and
don't know how to deal with them. Could you give me any suggestions?
1. After running the "Check Sample Homogeneity Using Covariance", VBM
toolbox output a chart and showed the range of homogeneity for all
subjects. I found some subjects were out of this range, is it means
that they are abnormal data? On this chart, some subjects were noted
by a red cross, what's that means? Should I cut them off in the next
analysis?
2. The result shows that, there are different abnormal subjects in
grey matter and white matter. So what should I do in the next
analysis? Should I just cut all of them off? Or cut off the abnormal
grey matter subjects when I analyze grey matter, and cut off abnormal
white matter subjects when I analyze white matter?
I made a PPT file to make my questions more clear, please check the
attachment. Thank you for your help and looking forward for your reply!
Yours,
Zhao
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