Dear expert,
I`m running a VBM analysis in a single stroke patient to explore posibles grey matter changes associated to treatment.
First, I draw the mask on time point 1 T1, then I corregister Time point 2 T1 to Time point 1 T1 and set, in both T1´s, lesion areas to 0 with mricron (draw--> mask image with VOI --> delete regions with VOI).
After, I used the "segment longitudinal data" option on CAT12. For this I entered the masked images generated previously
¿This seems correct?
Now, I`m not sure what statistical analysis should I use. The CAT12 manual gives and example for 1 group x 2 time points analysis and using a Flexible multifactorial analysis with 2 factors (subject and time). Are outcomes expected to be similar if using paired t test or within subject ANOVA (for more time point cases)?
What would be the correct to use in this case? a paired t test or a flexible factorial analysis?
When I tried to use the paired t-test the following error come out:
The following modules did not run:
Failed: Check design orthogonality and homogeneity
Even though the flexible factorial analysis do not seems adequate to me in this case, I still run it setting 1 factor:time. I believe it does not make sense in this case to include a "subject" factor since I have just 1 subject.
In this case, this error came out:
No executable modules, but still unresolved dependencies or incomplete module inputs.
The following modules did not run:
Failed: Factorial design specification
Skipped: Check design orthogonality and homogeneity
¿What is the best approach in this case?
I would highly appreciate any help on this
Maria Jose
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