Sorry for all the back and forth, let me know if there's anything I can send to make things clearer.
Age does not vary within subjects, so I tried "~1" but it failed. I also tried the "~PCLTotal" which also failed, although PCLTotal is the primary outcome measure I am interested in. Essentially, I have two sessions, one at 2 weeks and one at 6 months, and I want to assess if changes in connectivity between the 2 week and 6 month sessions relates to changes in the PCLTotal score (a self-administered symptom scale). Age and Gender are included as covariates. Does any of that help?
Edited 1 time(s). Last edit at 03/23/2021 02:54PM by kyrieamara.