Lee Friedman, Hal Stern, Gregory G Brown, Daniel H Mathalon, Jessica Turner, Gary H Glover, Randy L Gollub, John Lauriello, Kelvin O Lim, Tyrone Cannon, Douglas N Greve, Henry Jeremy Bockholt, Aysenil Belger, Bryon Mueller, Michael J Doty, Jianchun He, William Wells, Padhraic Smyth, Steve Pieper, Seyoung Kim, Marek Kubicki, Mark Vangel, and Steven G Potkin. 2008. “Test-retest and Between-site Reliability in a Multicenter fMRI Study”. Hum Brain Mapp, 29, 8, Pp. 958-72.
Abstract
In the present report, estimates of test-retest and between-site reliability of fMRI assessments were produced in the context of a multicenter fMRI reliability study (FBIRN Phase 1, www.nbirn.net). Five subjects were scanned on 10 MRI scanners on two occasions. The fMRI task was a simple block design sensorimotor task. The impulse response functions to the stimulation block were derived using an FIR-deconvolution analysis with FMRISTAT. Six functionally-derived ROIs covering the visual, auditory and motor cortices, created from a prior analysis, were used. Two dependent variables were compared: percent signal change and contrast-to-noise-ratio. Reliability was assessed with intraclass correlation coefficients derived from a variance components analysis. Test-retest reliability was high, but initially, between-site reliability was low, indicating a strong contribution from site and site-by-subject variance. However, a number of factors that can markedly improve between-site reliability were uncovered, including increasing the size of the ROIs, adjusting for smoothness differences, and inclusion of additional runs. By employing multiple steps, between-site reliability for 3T scanners was increased by 123%. Dropping one site at a time and assessing reliability can be a useful method of assessing the sensitivity of the results to particular sites. These findings should provide guidance toothers on the best practices for future multicenter studies.
Last updated on 02/24/2023