Hi Dost,
as Colm said, the same number of subjects is only needed for the creation of the template and is achieved via the images names put in the template_list file.
At the fslvbm_2 stage, all the images will be GM segmented anyway, but only those in the list will be taken into account when building the template. Then at the third stage, all the GM segmented images will be non-linearly registered to this "balanced" study-specific template...
Hope this helps,
Gwenaelle
--- En date de : Mar 16.9.08, Dost Ongur <[log in to unmask]> a écrit :
> De: Dost Ongur <[log in to unmask]>
> Objet: [FSL] uneven group sizes for VBM
> À: [log in to unmask]
> Date: Mardi 16 Septembre 2008, 21h40
> Hello,
> We are carrying out a VBM analysis but we have different
> numbers of subjects
> in the control and patient groups. The FSLVBM website
> indicates that you
> need the same number of subjects in each group to generate
> a reliable
> template.
> We have uneven numbers of subjects. We can't figure
> out a way to generate a
> template using the same number of subjects at the
> fslvbm_2_template stage,
> and then use the entire dataset at the fslvmb_3_proc stage.
> It seems that
> the generation of the template leads directly to the files
> used in the 3rd
> stage, and we are not sure how to add a few new subjects at
> that point.
> Thanks!
> Dost Ongur
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