help > RE: too much movement?
Feb 26, 2021  05:02 PM | Alfonso Nieto-Castanon - Boston University
RE: too much movement?
Hi Amy,

In Setup.Covariates (2nd-level) you will find (assuming the data was preprocessed in CONN) the variables QC_InvalidScans (number of outlier scans identified for each subject), QC_MaxMotion (maximum FD for each subject), and QC_MeanMotion (average FD across non-outlier scans for each subject), which you may use to determine whether it may be necessary to remove/disregard some subjects from your group-level analyses (e.g. if you run in CONN the Quality Assurance plot labeled "distribution of subject-level QC measures", that will list potential outlier subjects based on each of the selected measures - I typically recommend using QC_ValidScans and QC_MeanMotion). 

Originally posted by Amy Roy:
I am new to CONN. Previously when I analyzed resting state functional connectivity data I would examine the mean, max and min FD for each participant to determine whether to use their data. I cannot seem to find outputs in CONN that provide this information. So, how can I tell if a participant has too much motion to be included in the analyses? Is it assumed that because CONN uses scrubbing, that all participants are used regardless of the amount of movement? I would appreciate some guidance here as I am willing to remove participants with excessive movement but I am not sure how to determine this using the preprocessing outputs in CONN. I have patient groups where group membership may be related to movement so I need to be sure this is appropriately accounted for. 
Thank you

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Amy Roy Feb 26, 2021
RE: too much movement?
Alfonso Nieto-Castanon Feb 26, 2021