Dear Freesurfer team, We are currently doing a cortical thickness studies between a group of psychiatric patients (n=60) and controls (n=30). We tested several smoothing levels (15mm, 20mm, 25mm)
When setting an uncorrected threshold (such as p<0.005), we obtained several regions of decreased thickness, which are consistent with the pathology. However, when trying to correct for multiple comparisons using FDR ("Set Using FDR" button in qdec), the computed threshold is very high (e.g. 4.3 for 20mm smoothing) and, obviously, no significant regions are left. Did we do anything wrong in the analysis ? Thank you very much for your help, Yulia _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer