Dear Anderson,
Thank you for making PALM freely available - I'm new to it, and the first few test runs have worked like a charm!
The problem I'm facing now is how to adequately correct over multiple contrasts. I'm running an analysis in which I will need 6 pairwise comparisons (Patient vs controls, patients with sydrome 1 vs syndrome 2, patients with mild disease vs patients with severe disease - and vice versa). All use the same modality, EEG images from SPM12.
As I understand, this can be achieved in PALM using the option -corrcon, which does FWER over contrasts. Is this a Bonferroni correction? If so, power might be an issue, and I would want to try contrast-level correction with NPC.
How does the latter work in practice? Would I need to use -npccon -corrcon as command option? And in terms of interpretation, would it mean that partial contrasts are thresholded using the joint FWE threshold, or this incorrect?
Thanks for any help!
Eugenio
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