A Prospective Multi-Institutional Study of the Reproducibility of fMRI: A Preliminary Report from the Biomedical Informatics Research Network

Abstract. Functional magnetic resonance imaging (fMRI) has significantly contributed to understanding both normal and diseased human brains. Variability often exists in the magnitude, spatial distribution, and statistical significance of the resulting fMRI maps due to differences in equipment and other site-specific differences. In addition, because of costly imaging, demanding tasks, and analytical burden, understanding the effect of these differences may help develop an efficient pooling and comparison mechanism. Prospective multi-institutional repeated fMRI data were acquired recently in the first phase of the extensive Functional Imaging Research of Schizophrenia Testbed study, sponsored by the Biomedical Informatics Research Network (BIRN) in the US. Five “human phantoms, ” who were right-handed healthy males, were included in the study. These subjects repeatedly performed the same sensory-motor task over 10 of the 11 study sites on 2 separate visits per site. The effects of factors such as subject, study site, field strength, vendor, K-space, visit, and repeated run on the fMRI reproducibility were evaluated. Over 4 repeated runs per visit at each site, at a given binarizing activation threshold, we first calculate