Hi AFNI gurus, I am having an issue with 3dROIstats. Just some background, I have three groups H, L and SZ. I created a mask of regions that overlapped from two pairwise comparisons of these groups (areas that were significant for both the HvsSZ comparison and the HvsL comparison). So in other words, I extracted areas that showed up in both comparisons and made an ROI mask with each ROI having a separate value. The ROI mask has 37 values (autorange =37) but when I use it as the mask option when running 3dROIstats it only outputs select ROIs (specifically ROIs with values 4,5,6,13,16,17,22,29,30,33,35,37). It is likely that some of these ROIs are one voxel and I would understand why it would not output a mean for that but when looking at the cluster report (using the most conservative clustering settings) there should be at least 15 ROIs greater than 1 voxel and the 3dROIstats outputs only 12. Any thoughts? Thanks.