We haven’t looked at the test/retest for diffusion and that sounds too extreme, i.e. something that one could even visually spot. It is possible you have done something wrong in your processing?
The only thing that we can imagine is whether positioning in the scanner for test/retest has been considerably different and grad-nonlin differences make a big difference and were not included in the estimation. Matt. From: <hcp-users-boun...@humanconnectome.org<mailto:hcp-users-boun...@humanconnectome.org>> on behalf of HUA LI <hua3...@gmail.com<mailto:hua3...@gmail.com>> Date: Friday, November 30, 2018 at 3:16 PM To: "hcp-users@humanconnectome.org<mailto:hcp-users@humanconnectome.org>" <hcp-users@humanconnectome.org<mailto:hcp-users@humanconnectome.org>> Subject: [HCP-Users] DTI retest Dear HCP team, Do you have the reproducibility results for DTI metrics (FA and MD) based on the 46 test/retest data? I analyzed several subjects, but found a very large variation: abs(FA_test-FA_retest)/mean(FA_test,FA_retest) is >10% in white matter and >20% in gray matter. Hope to see if anyone got similar results. Thanks, Hua _______________________________________________ HCP-Users mailing list HCP-Users@humanconnectome.org<mailto:HCP-Users@humanconnectome.org> http://lists.humanconnectome.org/mailman/listinfo/hcp-users ________________________________ The materials in this message are private and may contain Protected Healthcare Information or other information of a sensitive nature. If you are not the intended recipient, be advised that any unauthorized use, disclosure, copying or the taking of any action in reliance on the contents of this information is strictly prohibited. If you have received this email in error, please immediately notify the sender via telephone or return mail. _______________________________________________ HCP-Users mailing list HCP-Users@humanconnectome.org http://lists.humanconnectome.org/mailman/listinfo/hcp-users
