Dr. Nichols,
Hello. I am using FSL scripts to extract information from
statistical map images in certain ROIs. I am doing this by placing a
threshold on the map and then finding information like: max z-score, mean
z-score, number of voxels etc. However, by chosing a threshold this way
(for example z=2.3) I am essentially using an uncorrected threshold. I
know that if I want to do a Bonferroni correction in the ROI I can divide
alpha by the number of voxels in the ROI. But what if I want to do an FDR
correction at alpha=0.5? Can I find the 95th percentile of all the z
values
in the ROI and use that as the threshold for the ROI? Would this then be
considered FDR corrected at the ROI level?
thank you for any feedback.
Jason.
Jason Steffener
Department of Radiology
New Jersey Medical School
Biomedical Engineering Department
New Jersey Institute of Technology
Newark, NJ USA
(973) 676-1000 x1545
http://web.njit.edu/~jrs3
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