Graphs displaying the diagnostic performance of mean fractional anisotropy (FA) and Shannon entropy (SE). Receiver operating characteristic curves measure the diagnostic performance of a given test based on the area underneath the curve, with large areas indicating high performance and smaller areas indicating poor performance. These graphs demonstrate that (A) mean FA performs acceptably differentiating patients with mild traumatic brain injury from control subjects, with a substantial amount of area under the curve. However, SE was an even better test to distinguish patients with mild traumatic brain injury, with a significantly greater area under the curve, indication better diagnostic performance. The difference becomes more pronounced in attempting to predict the presence of posttraumatic migraine, where, in C, mean FA performed poorly, with very little area under the curve, but SE continues to demonstrate excellent performance, with a relatively large area under the curve (D).