Dear Nádia,
An easy way would be to compute the average image across time points for
each subject and enter these images in a two-sample t-test.
Best regards,
Guillaume.
On 20/05/2021 17:33, N ádia Canário wrote:
> Hi all
>
> I'm doing a VBM longitudinal data analysis in two groups with two time points. I followed the cat12 tutorial regarding longitudinal data in two groups and i have done the F test to explore a main effect of group using the contrast suggested in the tutorial.
>
> Now i'm trying to compare one group against the other using both time points (t test) but the tutorial does not provide a contrast for that. I tried 1 1 -1 -1 but cat12 doesn't accept this contrast as valid one.
>
>
>
> Do you have any suggestion how to do this?
>
>
>
>
> Thank you
>
> Nádia Canário
>
--
Guillaume Flandin, PhD
Wellcome Centre for Human Neuroimaging
UCL Queen Square Institute of Neurology
London WC1N 3BG
|