Test-retest reliability was calculated using an intraclass correlation coefficient (ICC) (NDI ICC=.50; 95% confidence interval [CI], .25-.67; NRS ICC=.76; 95% CI, .51-.87). The area under the curve was .83 (95% CI, .75-.90) for the NDI score and .85 (95% CI, .78-.93) for the NRS score for determining between stable and improved patients. Thresholds for the minimum clinically important difference (MCID) for the NDI were 19-percentage points and 1.3 for the NRS.