Hello All, I have pre-processed a subject that has T1 scans at 3 time points using the freesurfer cross-sectional and longitudinal methods. The results show a lot of variability. I have attached the plots. Any advice would be much appreciated.
Thanks, Pradeep On Wed, Apr 15, 2015 at 5:26 PM, Pradeep <tprad...@gmail.com> wrote: > Hello All, > > I have pre-processed a subject that has T1 scans at 3 time using the > freesurfer cross-sectional and longitudinal methods. The results show a lot > of variability. I have attached the plots. Any advice would be much > appreciated. > > Thanks, > Pradeep > > On Wed, Jun 4, 2014 at 12:03 PM, Alexandru Hanganu <al.hang...@yahoo.ca> > wrote: > >> Thank you very much for your answer Bruce ! >> >> have a nice evening, >> >> Alex. >> >> >> Le 3 juin 14 7:6, Bruce Fischl a écrit : >> > Hi Alex >> > >> > I would think that longitudinal analysis is still the way to go as we >> try >> > to improve both reliability and sensitivity using the fact that we have >> > multiple scans/subject. >> > >> > cheers >> > Bruce >> > On Tue, 3 Jun 2014, Alexandru Hanganu wrote: >> > >> >> Hello Everyone, >> >> >> >> could someone please give us an advice about which method you consider >> is >> >> the best for our study ? >> >> >> >> we have two groups with MRI at Time 1. Each group received medication. >> After >> >> this we performed another MRI at Time 2 after 2 weeks. >> >> >> >> The best method for this study is a longitudinal one or a >> cross-sectional >> >> GLM ? >> >> >> >> We consider that the distance between the time points is too small, >> and the >> >> longitudinal method is not the best choice. Hence, this study should be >> >> treated as a cross-sectional one. In this case we think about >> performing a >> >> simple GLM with the contrasts: >> >> 0.5 0.5 0.5 0.5 >> >> or 1 -1 -1 1 >> >> >> >> for the groups: >> >> 1) grp 1 time 1 >> >> 2) grp 1 time 2 >> >> 3) grp 2 time 1 >> >> 4) grp 2 time 2 >> >> >> >> we are searching to see whether medication had any impact on the >> cortical >> >> morphology in each group and between the groups. >> >> >> >> Thank you ! >> >> Best regards, >> >> Alex. >> >> >> >> >> > _______________________________________________ >> > 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. >> > >> > >> >> _______________________________________________ >> Freesurfer mailing list >> Freesurfer@nmr.mgh.harvard.edu >> https://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.
