For VBM see e.g. Pell et al (2008) NeuroImage
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From: Michelle Kibby [[log in to unmask]]
Sent: Monday, January 21, 2013 11:27 AM
To: Watson, Christopher
Cc: [log in to unmask]
Subject: Re: [SPM] group size
Thank you for the resources. Would these same issues apply to VBM?
On Fri, Jan 18, 2013 at 9:12 PM, Watson, Christopher <[log in to unmask]<mailto:[log in to unmask]>> wrote:
I can't think of an inherent issue with this. For some literature, you can check out Thirion et al (2007), NeuroImage, and go from there. Jeanette Mumford and Tom Nichols also have several publications dealing with power in group fMRI analyses.
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From: SPM (Statistical Parametric Mapping) [[log in to unmask]<mailto:[log in to unmask]>] on behalf of Andrew Martin [[log in to unmask]<mailto:[log in to unmask]>]
Sent: Friday, January 18, 2013 9:51 PM
To: [log in to unmask]<mailto:[log in to unmask]>
Subject: [SPM] group size
Dear all
Is there any support for both target and control size being the same size (approximately) in fMRI studies. If one group was 15 and the other 30 would this pose any statistical problems (power to detect an effect in both groups etc)?
Thanks
Andrew
--
Michelle Y Kibby, PhD
Associate Professor in Clinical Child Neuropsychology
Dept. of Psychology
Southern Illinois University-Carbondale
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