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Hi Forum, I was hoping to get some help on few questions regarding interpretation of vertex analysis results and multiple comparisons correction: 1. What is the appropriate multiple comparisons correction for vertex analysis results in randomize?: - 1a Should TFCE be 2D or 3D? - 1b In FDR, by "adjusted" do you mean the Yekutieli D, Benjamini Y (1999) adjustment? 2. How to interpret results? - 2a With dichotomous variables, is the contrast result one-directional? So, if I code Group1 as +1 and Group2 as -1, and my contrast is: +1 (as in the example on the FSL website), I see both regions that have significant expansion AND regions that have significant atrophy in Group1 as compared to Group2? And, since the new version of vertex analysis doesn't produce the surfaces with arrows anymore, how do I tell, for a region that is significant, which is the direction of the difference? - 2b With covariates: are results interpreted similarly to the dichotomous variables -- so I only need 1 contrast (e.g., +1) and not that AND its reverse (e.g., "-1")? I guess the intuition would be that there are 4 possibilities (1, regions that expand in positive correlation with the covariate; 2, regions that atrophise in positive correlation with the covariate; 3, regions that expand in negative correlation with the covariate; 4, regions that atrophise in negative correlation with the covariate) but the latter 2 are entailed by the former 2? Thank you very much. Any help is greatly appreciated. Evan Lutkenhoff