Dear SPM experts,
Recently I read about a PET study, in which after the data were processed (SPM2, 2x2x2mm voxel, 8mm smoothing, paired t-test) and a VOI defined, authors used the following way of correction for multiple comparisons:
a Bonferroni-corrected cluster-level P value for a cluster in the VOI was calculated as a function of the cluster volume:
Pcorr=P*Sv/Cv
where Sv = number of voxels in the VOI; Cv = cluster volume.
I wonder if this is a safe way to obtain a corrected P value for clusters in a VOI?
If it is ok, in which case this method can be preferred over the one used by SPM for cluster p value correction?.Thanks,
Victor