Hi ZhiLiangLong, what you have set up probably does not make sense. By
using gender as a covariate (male=1 and female=2), you are saying that
you expect females to be twice as thick as males.
doug
ZhiLiangLong wrote:
Hi, FS experts:
I'm scanning freesurfer pages about FSGD files here:
http://surfer.nmr.mgh.harvard.edu/fswiki/Fsgdf4G1V
and i'm interested in one contrast file(the example of Contrast 5
right-left.intercept.mtx). The original FSGD file is list as follows:
GroupDescriptorFile 1
Title OSGM
Class MaleRight
Class MaleLeft
Class FemaleRight
Class FemaleLeft
Variables Age
Input subject1 MaleRight 30
Input subject2 MaleLeft 40
Input subject3 FemaleRight 50
Input subject4 FemaleLeft 60
The contrast file is : 0.5 -0.5 0.5 -0.5 0 0 0 0, meaning to exame the
difference between Righties and Lefties regressing out the effects of
gender and age.
Now i consider gender as the covariate variable ('1' represents the
Male and '2' represents the Female), and i setup a new FSGD file:
GroupDescriptorFile 2
Title OSGM
Class Right
Class Left
Variables Age gender
Input subject1 Right 30 1
Input subject2 Left 40 2
I also want to exame the difference as suggested above, and I setup
the new contrast file as :1 -1 0 0 0 0.
My question is that : are the new FSGD and contrast files correct to
exame the difference as suggested by original FSGD and contrast files?
------------------------------------------------------------------------
_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
--
Douglas N. Greve, Ph.D.
MGH-NMR Center
gr...@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422
Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html
_______________________________________________
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
The information in this e-mail is intended only for the person to whom it is
addressed. If you believe this e-mail was sent to you in error and the e-mail
contains patient information, please contact the Partners Compliance HelpLine at
http://www.partners.org/complianceline . If the e-mail was sent to you in error
but does not contain patient information, please contact the sender and properly
dispose of the e-mail.
