Dear SPM fellows,
I'd like to seek some opinion on our test analysis.
We have 30 subjects and 30 control who are tested with the same fMRI
paradiagm. Individual results are analysed (60 con*.img). To analysis
the group effect, we performed a two sample t test (subject group and
control group are different) by selecting first 30 subjects from test
group (con*.img) and selecting the next 30 subjects from control group.
In the group definition, we entered 30 '1' and 30 '2'. After all the
selections (all none/omit), we entered a contrast 1 -1 to evaluate the
group effect. Is that true that the contrast is a population inference
(RFX) rather than a FFX within the 60 subjects we collected? We'd like to
do a RFX.
Another question is: If we have a single batch of subjects who undergo a
treatment and fMRI were acquired before and after the treatment. What
kind of test should I do to see if the treatment is effective to the group
in a whole and to the population (if possible)?
Thanks.
Kelvin
|