Dear FSL users,
I have two group of subjects one is Contact-Control and another is Concussed. In each group there are both male and female.
Now I want to see interaction of sexes in groups. The study is multi-site, 3 sites, 2 type of scanners.
So I thought of 2 possible ways
Method 1
design.mat
Group1 Group2 Sex(Group1) Sex (Group2) CoV1(age) Cov1(Site) CoV3(Scanner)
1 0 2 0 18 1 1
1 0 1 0 19 1 2
1 0 2 0 20 2 1
1 0 1 0 19 3 2
0 1 0 1 21 2 1
0 1 0 2 22 3 2
0 1 0 2 19 2 1
0 1 0 1 20 2 1
......
......
2= female 1-male
and the design.con
Group1 Group2 Sex(Group1) Sex (Group2) CoV1(age) Cov1(Site) CoV3(Scanner)
0 0 1 -1 0 0 0 (interaction 1)
0 0 -1 1 0 0 0 (interaction 2)
0 0 0 1 0 0 0 (positive correlation)
0 0 0 -1 0 0 0 (negative correlation)
0 0 1 0 0 0 0 (positive correlation)
0 0 -1 0 0 0 0 (negative correlation)
Another alternate approach I thought of is
Method 2
design1.mat
MALE FEMALE MALE (GROUP) FEMALE(Group) CoV1(age) Cov1(Site) CoV3(Scanner)
1 0 2 0 18 1 1
1 0 1 0 19 1 2
1 0 2 0 20 2 1
1 0 1 0 19 3 2
0 1 0 1 21 2 1
0 1 0 2 22 3 2
0 1 0 2 19 2 1
0 1 0 1 20 2 1
......
......
where 2=Contact-Control and 1=concussed.
and design1.con looks something like
MALE FEMALE MALE (GROUP) FEMALE(Group) CoV1(age) Cov1(Site) CoV3(Scanner)
0 0 1 -1 0 0 0 (interaction 1)
0 0 -1 1 0 0 0 (interaction 2)
0 0 0 1 0 0 0 (positive correlation)
0 0 0 -1 0 0 0 (negative correlation)
0 0 1 0 0 0 0 (positive correlation)
0 0 -1 0 0 0 0 (negative correlation)
Could you please specify which approach is appropriate in this regard?
Which will give me interaction of sexes in groups?
Thanking you
Sourajit
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