External Email - Use Caution Hi Dr. Greve,
Thanks for your quick reply. Could you please give me more details how can I check this whether its because of noise or its because of less CV difference? I am not sure what method/way is the best and commonly used to confirm these factors. Thanks. On Tue, Jul 24, 2018 at 7:06 AM, Douglas Greve <dgr...@mgh.harvard.edu> wrote: > your results could have vanished after ICV correction for one of two > reasons: the CV difference became less or the values became noisier (or a > combination). So check in your data which one of those things happened. > > > On 7/23/18 8:30 PM, Martin Juneja wrote: > > External Email - Use Caution > Hello experts, > > I am interested in identifying regions of interest by comparing cortical > volume (CV) between controls and patients. > > After including age and sex as my covariates, I identified regions X1 and > X2, which showed significantly lower CV for patients (as compared to > controls). > > But after I include ICV as another covariate, my results show that for > none of the areas there is any significant difference in CV, i.e. my > results vanish. > > When I checked subjectwise ICV for each group, I found that there is > almost significant difference (two-sampled t-test, p = 0.067) in ICV > between two groups, but interestingly mean group ICV for patients group was > larger compared than mean ICV for controls. But as I said earlier, regions > X1 and X2 had significantly lower CV for patients (as compared to > controls), when I didn't include ICV as covariate. > > Could you please help me in interpreting these results? Is there any > advice regarding inclusion of ICV as covariate? Or my results are purely > because of differences in ICV between groups, and there is no real findings > regarding the regions identified (X1 and X2)? > > Thanks a lot ! > > > _______________________________________________ > Freesurfer mailing > listfreesur...@nmr.mgh.harvard.eduhttps://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer > > > > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer > > > The information in this e-mail is intended only for the person to whom it > is > addressed. If you believe this e-mail was sent to you in error and the > e-mail > contains patient information, please contact the Partners Compliance > HelpLine at > http://www.partners.org/complianceline . If the e-mail was sent to you in > error > but does not contain patient information, please contact the sender and > properly > dispose of the e-mail. > >
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