Dear Anderson and FSL team,
I have a doubt and I would be greatly appreciate your experience in order to set the better design to study my hypothesis.
I have one variable X that was measured only at Time0 (basal) and I have another variable that was measured at Time0, Time1, Time2, Time3 and Time4 (repeated measures during four years) over three different groups that has been splitted taking into account variable X at Time0. I think I should use a mixed effect model followed by Kaplan and Meyer graphics and Cox Regression to calculate Hazard Ratio value as well as p value associated.
From a neuroimaging point of view. I have only 45 MRI scans T1 (not very well quality and I had problems with registration to template even after removing artefacts and deleting several scans (from 404 I have only 45...with same acquisition parameters and same machine). I had to performe registration with another toolbox and the results were very good. The fact is that I will like to conduct and analysis to see the effect of variable X over another variables
I have the hypothesis that status at variable X will have effects over another variable Y that was measured at Time0, Time1, Time2, Time3 and Time4 (repeated measures during four years). I will like to test this hypothesis either with MRI and fMRI. Here, my sample is small enough to prevent me to split it in three groups, so I consider all my sample as just one group. My first thought was to conduct this kind of analysis taking into account variable X at Time0 and variable Y at time4. But I think it is far more interesting to conduct a repeated measures analysis in order to see the changes in structural MRI and fMRI at rest regarding to see the effects of variable X over variable Y in structural MRI and functional fMRI along 4 years. But, I have never done this kind of analysis and I am pretty lost regarding the design I would have to conduct using GLM (in the case of structural MRI) and FEAT in the case of fMRI at rest). I know that with fMRI I have to correct by motion parameters (6) and by CSF as well as WM signal...but I am not able to imagine how to conduct this kind of analysis taking into account that, for example, motion parameters, CSF and WM signals will be different for every individual scan at every year....
Any help with this issue would be highly appreciate.
