Hello FSL Users,
We processed our pCASL dataset using BASIL with the --spatial option.
The original dataset had a resolution of 3.5x3.5x3.5 mm.
All the subjects were then normalised to MNI Space and have a resolution of 2 mm isotropic.
Now, we wanted to perform group level analysis on two groups to see if any regions have statistically significantly different CBF.
So, we smoothed the (already smoothed) normalised perfusion map using 4mm Gaussian Kernel (using the command:
fslmaths each_subject_perfusion -kernel gauss 1.69866 -fmean each_subject_smoothed_perfusion_map)
Then we used randomise to compare 2 groups and used 4mm variance smoothing inside randomise. Here is the command:
randomise -i my_4d_2grp_concat_files -o comp -d design.mat -t design.con -D -m MNI_152_t1_2mm -v 4 -x -T -R --uncorrp
and found significantly different regions consistent to our hypothesis.
We were just wondering if our statistical analysis pipeline is right?
In addition, if anybody could tell us how do we extract FWE corrected cluster map from tstat* map obtained in the previous step. (Question really is what threshold to input in -c option of randomise?)
We really appreciate the time and suggestion to solve our problem.
Thank you.
Regards
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