Dear All,
I am puzzled by the descriptions of TBSS--fslview
in the practical and the TBSS-website.
(1) In the practical of 'Analysis of Diffusion-Weighted MR Data
(the last paragraph of
http://www.fmrib.ox.ac.uk/fslcourse/lectures/practicals/fdt/index.htm),
... Thresholding clusters at 0.949 (corresponding to thresholding the
p-values at 0.05, because randomise outputs p-values as 1-p for
convenience of display - so that higher values are more significant) shows
several areas of reduced FA in the MS patients.
The following shows unthresholded t-stats in red-yellow and thresholded
clusters in blue:
fslview MNI152 mean_FA_skeleton -l Green -b 2000,8000 tbss_tstat1 -l
Red-Yellow -b 1.5,3 tbss_maxc_tstat1 -l Blue-Lightblue -b 0.949,1
(2) But in the TBSS
(http://www.fmrib.ox.ac.uk/fsl/tbss/index.html), the description
fslview MNI152 mean_FA_skeleton -l Green -b 2000,8000 tbss_tstat1 -l
Red-Yellow -b 3,6 tbss_tstat2 -l Blue-Lightblue -b 3,6
...The cluster p-value images (fully corrected for multiple comparisons
across space) are tbss_maxc_tstat1 and tbss_maxc_tstat2 (note, these are
actually 1-p for convenience of display, so thresholding at .95 gives
significant clusters).
Does any one know why 'fslview' in the two locations use different '-b'
values?
Many thanks in advance
Rhuang
