Reliability Of Functional Connectivity Measures In Resting-State Test-Retest FMRI Data.

The statistical link between spontaneous fluctuations occurring in different parts of the brain can provide insights into its functional organization. Here, we used high-quality resting-state fMRI (rs-fMRI) data acquired with a test-retest paradigm to assess the reliability of several functional connectivity (FC) metrics, some of which rarely used in the current literature. After applying time/frequency methods to generate FC matrices, we restricted our focus on individual edges through different statistical measures, including but not limited to the intra-class correlation coefficient (ICC). We found that full correlation and magnitude square coherence yielded more reproducible measurements than the other metrics, as revealed by ICC values. These results have important implications when choosing metrics for quantifying FC in rs-fMRI studies, adding novel information to the current panorama of information on the test-retest reliability topic.