Responsiveness and validity of the Normal Hand Score in patients undergoing carpal tunnel decompression

This study describes the measurement properties of the Normal Hand Score in patients undergoing carpal tunnel decompression (CTD). We identified 1893 episodes of CTD over a 6-year period. Paired pre- and postoperative QuickDASH, Normal Hand and satisfaction scores were available for 1006 episodes (53%; mean follow-up of 12 months). The effect size, minimum clinically important change (MCIC) and patient-acceptable symptom state (PASS) were calculated using anchor-based methodology and receiver operating characteristics (ROC) curve analyses. Mean Normal Hand Score improved from 48 (SD 20) preoperatively to 78 (SD 24) postoperatively ( p < 0.001). The MCIC was 18 points and the area under the ROC curve (AUC) was 0.88 (95% confidence interval [CI]: 0.85 to 0.92) demonstrating excellent fit. The PASS was 61 and the AUC was 0.94 (95% CI: 0.91 to 0.96) demonstrating outstanding fit. The Normal Hand Score has excellent performance characteristics, including appropriate responsiveness and acceptable criterion validity. This analysis supports its use as an adjunct to patient-reported outcome measures after CTD. Level of evidence: II