Dear SPM expert,
I am performing a paired t test analysis using SPECT images. Unfortunately, I get quite large p corrected values (i.e. 0.9 or so) while getting small uncorrected p values (0.001). As such it looks like a type I error. Estimation with bayesian makes things a little bit better but on a marginal basis.
When looking at several papers with SPECT, authors get a corrected p value around 0.01 with images that are about the same as mine (it is SPECT after all). However, they performed grey mater segmentation. Did this segmentation improve so significantly the stats ? Furthermore, what are the actual images to insert in the analysis (grey matter segmented, white matter ???)
Thanks in advance
Charles-Henri
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