This page describes the FreeSurfer Group Descriptor (FSGD) File Format (Version 1) as of 11/12/02. FSGD is a way to describe a group of subjects and their accompanying data. This can include class membership and other continuous varibles (eg, age). The nice thing about the FSGD is that various FreeSurfer programs can automatically compute the design matrix from an FSGD file.
The FSGDF is used by mri_glmfit, tksurfer, tkmedit. They are created automatically by qdec. The FSGD format uses tags to identify information.
- Example of a legal file:
GroupDescriptorFile 1 Title MyTitle Class Class1 plus blue CLASS Class2 circle green SomeTag Variables Age Weight IQ Input subjid1 Class1 10 100 1000 Input subjid2 Class2 20 200 2000 #Input subjid3 Class2 20 200 2000 DefaultVariable Age
- Notes:
* The first line must be "GroupDescriptorFile 1".
* Title is not necessary. This will be used for display.
* Class only needs the class name, the next two items will be used in the display.
* The third input is ignored.
* DefaultVariable is the default variable for display.
* SomeTag is not a valid tag, so it will be ignored.