Responsiveness and Minimal Clinically Important Difference of the Chinese Version of the Motor Function Measure-32 in Children and Adolescents with Duchenne Muscular Dystrophy

Abstract

ABSTRACT Purpose: This study aimed to examine the responsiveness and minimal clinically important difference of the Motor Function Measure 32-Chinese version (MFM 32-CN) in children and adolescents with Duchenne muscular dystrophy (DMD). Methods: This observational, prospective cohort study assessed changes in motor function over 12 months using the MFM 32-CN in 108 pediatric patients with DMD. Results: Moderate to high internal responsiveness was found for MFM total, D1, and D2 scores (SRM = 0.46–0.83). Sufficient external responsiveness was observed in all MFM scores, as determined by a good correlation with the Patient Global Impression of Change (PGIC) ratings (r = 0.54–0.72, p < .01). The estimated MCID values derived from different anchor-based methods ranged from 4.7 to 6.0, with a median of 5.0 points (%). Conclusion: The MFM 32-CN demonstrates sufficient internal and external responsiveness as a measure of motor function in children and adolescents with DMD. The present study established the MCID of MFM-32 in pediatric patients with DMD.