Dear Collegues,
I am trying to desing a GLM to show areas in the white matter of the the barin which have progressive decrease in FA during one year. To make it simpler I explain this for 2 subjects. Data are for 2 subjects for 5 timepoints( 0,1,3,6,12 month) during one year. I designed below GLM:
Group EV1 EV2 EV2
Inteceps Subject1 Subject2 Contrast EV1 EV2 Ev3
1 1 1 0 Subject 1 0 1 0
1 1 1 0 Subject2 0 1 0
1 1 1 0
1 1 1 0
1 1 1 0
1 1 0 1
1 1 0 1
1 1 0 1
1 1 0 1
1 1 0 1
I also did this for only one subject as below:
Group EV1 EV2
Inteceps Subject1 Contrast EV1 EV2 Ev3
1 1 1 Subject 1 0 1 0
1 1 1
1 1 1
1 1 1
1 1 1
When I checked the result (choosing one area and check the FA value in each 5 time points), the result was not correct! In my example area, there were a decrease in first 2 time points then increase and again decrease. Therefore it showed that the GLM that I designed was not correct.
Now I am wondering how I can desing something like this. What is the appropriate GLM design?
I would highly appreciate if you could give me a hand and give me a suggestion.
Best Regards,
Gelareh
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