Freesurfer uses a morphed spherical method to average across subjects for a GLM group analysis with the QDEC tool. Tkmedit and Tksurfer are the editing and visualization tools included in the package, but they will be replaced by Scuba when it Assuming that all 'reconall all' processing has been completed for all subjects in the study, FreeSurfer's Qdec application can be used to perform intersubjectgroup averaging and inference on the cortical surface.
Introduction. This tutorial is designed to introduce you to the" commandline" group analysis stream in FreeSurfer (as opposed to QDEC which is GUIdriven), including correction for multiple comparisons.
While this tutorial shows you how to perform a surfacebased thickness study, it is important to realize that most of the concepts learned here apply to any group analysis [Freesurfer group analysis with qdec Nick Schmansky nicks at nmr. mgh. harvard. edu Mon Feb 1 13: 40: 15 EST 2010. Previous message: [Freesurfer make a mask where the patient group showed significant reduction, and using it for further correlational analyses with clinical variables, Surfacebased Group Analysis in FreeSurfer!
You still have to specify contrasts! QDEC! Limited to 2 discrete variables, 2 levels max! Limited to 2 continuous variables. 17 Commandline Processing Stages! Assemble Data (mrispreproc)!
Resample into Common Space! Smooth! doug Roser Sala wrote: Hi, We are doing a group analysis using qdec with two groups, and we would like to include gender and age as covariates. Which is the best option in order to perform a simple ttest (group1group2 and group2group1) and including the two covariates? Tutorials Qdec Group Analysis This tutorial will take you through the same group analysis has the previous tutorial, but using FreeSurfer's QDEC, a GUIbased program.
If you are taking one of the formally organized courses, Surfacebased Group Analysis in FreeSurfer Create your own design and contrast matrices Create an FSGD File FreeSurfer creates design matrix You still have to specify contrasts QDEC FreeSurfer Group Descriptor (FSGD) File Qdec: A groupanalysis tool for Freesurfer Nick Schmansky Martinos Center for Biomedical Imaging Tutorials Group Analysis. This tutorial is designed to introduce you to the" commandline" group analysis stream in FreeSurfer (as opposed to QDEC which is GUIdriven), including correction for multiple comparisons.
While this tutorial shows you how to perform a surfacebased thickness study, it