I would like to customize the xcp_d motion scrubbing. Specifically, I would like to:
Target volumes that exceed FD or DVARS thresholds. It would be nice to have the option to customize this boolean logic.
Target neighboring volumes (e.g., 2 before and 1 after). Again, it would be nice to customize which neighboring volumes are included or base the volumes included on scan TR.
Remove participants/scans with too many scrubbed volumes (e.g., good scan time ≤ 7 min, good volumes ≤ 75% total scan).
Interpolation between scrubbed volumes.
Does anyone know (1) if these options are already feasible with xcp_d, (2) if not, how to incorporate them into the xcp_d pipeline. I have already run all of my scans through fMRIPrep.
I’m also happy to receive feedback; for instance, are some of these features unnecessary or problematic, do you use these options in your own analyses, are they analysis-specific, and how have you chosen values (i.e. what is your reasoning for them [citations are appreciated])?
These are all totally reasonable requests. Implementing them in xcp_d could be tough, but I think it’s worth opening two separate feature request issues on GitHub.
I think this might be something to address in your group-level sample selection, rather than within xcp_d. The QC files xcp_d outputs should make it easy to flag any bad subjects, although we could work on a more BIDS-compliant way to output that kind of info.