Hi Gwenaelle,
Thank you for such a prompt reply.
>> 2) Generate a ROI mask and use that with the -m
>> function in
>> randomise, with or without the TFCE option.
> Right. With TFCE or cluster-based correction, you're
> still looking at "voxel-skeleton wise" results and not
> at the significance of the global change of FA within
> your ROI...
So, if I interpret you, and the list correctly, there's three ways of
analysing ROIs:
1) use voxel-wise tbss analysis
2) don't use tbss, but use fslmaths to find the mean FA within the
whole cerebellum including grey matter.
3) use the skeleton output from tbss but generate a mean of the FA in
the ROI. ALthough it's probably better to do 1).
Are there restrictions about doing 1)? Would randomise results be
valid for voxel-wise analysis of a small ROI?
Thanks for your other advice, I'll give the masking procedures a go.
Regards
Suzanna
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