I know that this may be a very dummy question but I did not find any
advice or documentation from other sources.
There has been a very substantial change in the GUI for the statistical
models in the new SPM5. We are interested in a very basal group
comparisons using VBM.
3D T1-Images where segmented, modulated and normalized with the new
segmentation tool of SPM5 (unified model) and smoothed with 12mm Gaussian
kernel.
Unfortunately the “basic models” GUI of SPM2 is gone (allowing for simple
ANOVA with e.g. 2 groups) and has been replaced with the “2nd level
analysis” or “basis models” (PET) but there is no obvious difference
between the later two.
My basic question is:
Which model should we use for a simple 2-group comparison e.g. with
dementia patients?
One sample t-test and defining the groups with a covariant vector (0 or 1
for group assignments).
Or 2-sample t-test with groups assigned to group1 and 2 in the GUI
Or even factorial designs?
I really would appreciate any advice on this issue or maybe a suggestion
where to find a documentation. The original SPM documentation does not
help us very much on this issue.
Thanks.
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