There is not a set number as it depends on the size of your effect. If your effect size is 0, then no number of subjects is enough. To answer this question, you need a power analysis. Having said that, people often shoot for 20 because you get to the knee of the DOF-vs-p-value curve on a t-test.
Not sure what you mean by "intra-individual" analysis.
doug
On 07/09/2013 03:40 PM, Nooshin Zadeh wrote:
Dear Freesurfer group
I am interested to do group analysis on my data. If I want to do inter-individual group analysis, what is the minimum number of subjects I need to have? Also if I want to do intra-individual analysis, what is the best way in FS? I appreciate your time and your help.
Thanks a lot,
Nooshin
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