Tynan Stevens1, Steven Beyea2, Ryan D'Arcy3, David Clarke1
1Dalhousie University, Halifax, Nova Scotia, Canada; 2NRC, Halifax, Nova Scotia, Canada; 3Frasier Health Authority, Surrey, British Columbia, Canada
The Rombouts overlap coefficient (Roverlap) is used extensively in fMRI reliability research. While it is widely recognized that this coefficient depends on analysis threshold, existing studies do not agree on the precise relationship between Roverlap and threshold, and so no clear strategy has been employed across studies. We argue that individual variability in the Roverlap-threshold relationship reduces the information available in group level Roverlap results. This variability likely contributes to the inconsistent findings in the literature to date. We thus suggest that control of reliability is best conducted at the individual-level, as group trends may not be truly representative.