Covariates Regression in Statistical Analysis

Hello REST team,

First of all, thanks for the development of such a adequate software to analyse resting state fMRI data, and for maintaining it as an open source.

Now, I have some doubts about how to use the Statistical Analysis utility in REST, or more concretely, in dpabi. I have adquired resting state fMRi data of twenty subjects (normal controls) in three different conditions. We are using tDCS to modulate brain activity, and have proved two different montages of electrode location, and a sham stimulation condition. Moreover, I have preprocessed the data with SPM8, and now I want to calculate ALFF and fALFF resting state metrics to evaluate the differences in ALFF and fALFF in the regions/networks that were targeted by the stimulation. Then, I have used DPARSFA to detrend, calculate ALFF and fALFF measures, and filtered (for ALFF) and regressed out the following covariates: six motion parameters, global signal, white matter signal and CSF signal. 

So, DPARSFA have generated the following folders: 

Masks
Results
SUBJECTSD
SUBJECTSDC
SUBJECTSDCovs

and there are also the folders SUBJECTS and RealignParameter.

Firstly, I have doubts about the content of the folder SUBJECTSCovs, where there are the following documents:

ROI_OrderKey_SubjX.tsv

ROICorrelation_SubjX.mat
ROICorrelation_SubjX.txt

ROICorrelation_FisherZ_SubjX.mat
ROICorrelation_FisherZ_SubjX.txt

ROISignals_SubjX.mat
ROISignals_SubjX.txt

(each one for every subject)

And the point is that I am not sure of what that documents mean, and what are they use. Also, I have to say that I have seen the video curses many times, and looked for deeply in the forum.

Furthermore, and the most relevant question, is about how to do the statistical analysis in REST or dpabi, and not the basic procedures (what I think is the less clear thing in the video course). I am not sure if I have to enter the covariable's signals extracted by DPARSFA in REST or dpabi (the 6 motion parameters, global, WM and CSF sgnal) in order to do the statistical analysis, and if it is required, how to do it, and what documents I should use to enter in the statistical analysis as covariables. Or maybe these signals are already extracted from the ALFFMaps and fALFFMaps, and I just need to enter the maps in the Statistical Analysis utility and run it.

Finally, I have deducted that, for the experimental procedure we have used, the most adequate statistical materic is the ANOVA with Repeated Measures, as it have been implemented in dpabi. Am I correct?

Thanks in advance for your help. This software have been very helpful for us.

All the best,

Cristian.