Dear FreeSurfer Team,

We are analyzing some longitudinal data (baseline [0], 6 months, 1 year, 1.5 years) using FreeSurfer 7.4.1.
We already analyzed two timepoints (basline[0] and 6 months) but now we are trying to look at 4 timepoints in total.

I was wondering what the best way would be to do this. For the longitudinal processing, should we create 3 bases/within-subject templates between 0-6 months (this is already done), 0-1year, 0-1.5years), or between 0-6months, 6months-1year, 1year-1.5years. Or both?

Also, is it okay to correct/edit only the bases?

After the longitudinal processing, can we create a Longitudinal Table and apply the two-stage model (LongitudinalTwoStageModel) method? Or because of the 4 time points, we need to apply something else.

Thank you for your help in advance!

All the best, Eszter