Dear Freesurfer experts,

I am trying to do a longitudinal repeated measures ANOVA 2x2, with two groups (experimental vs control) and two time points (pre and post treatment).

Although I have run a paired t-test, now I would like to do a repeated measures anova 2x2, since I am doing the same analyses with other data in other softwares.

I am trying to follow the tutorial MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be https://surfer.nmr.mgh.harvard.edu/fswiki/RepeatedMeasuresAnova, but I have several doubts when designing the FSGD file as well as the contrasts.

How should it be the FSGD file?

I have seen in a previous post the following design for the same number fo groups and time points:

GroupDescriptorFile 1

Class Subject1

Class Subject2

Variables Tp1vsTp2.GrExp Tp1vsTp2.GrControl

Input Subject1_time1 Subject1 1 0

Input Subject1_time2 Subject1 -1 0

Input Subject2_time1 Subject2 0 1

Input Subject2_time2 Subject02 0 -1

Design matrix:

1 0 1 0

1 0 -1 0

0 1 0 1

0 1 0 -1

Contrasts (.mtx files):

Tp1vsTp2.GrExp 0 0 1 0

Tp1vsTp2.GrControl 0 0 0 -1

Interaction 0 0 1 -1

Would this design be the correct one to use in this case?

Alternatively, could it be this the correct one?

GroupDescriptorFile 1

Class Subject1

Class Subject2

Variables Tp1vsTp2 Groupxtime

Input Subject1_time1 Subject1 1 1

Input Subject1_time2 Subject1 -1 -1

Input Subject2_time1 Subject2 1 -1

Input Subject2_time2 Subject02 -1 1

Design matrix:

1 0 1 1

1 0 -1 -1

0 1 1 -1

0 1 -1 1

Contrasts (.mtx files):

Tp1vsTp2 0 0 1 0

Groupxtime Interaction 0 0 0 1

Thank you very much in advance.

Kind regards,

Agurne

Neuropsychology of Severe Medical Conditions Research Team

Dpt of Methods and Experimental Psychology
Faculty of Psychology and Education

University of Deusto

neurolab.deusto.es

Avda. de las Universidades 24,

48007, Bilbao (Spain)

Phone: +34 944139000 (ext. 3015)