Related Experiment Video
Updated: May 6, 2026
Measurements of Motor Function and Other Clinical Outcome Parameters in Ambulant Children with Duchenne Muscular Dystrophy
Published on: January 12, 2019
Development and validation of a motor function classification in patients with neuromuscular disease: the NM-score
C Vuillerot1, P Rippert, S Roche
1L'Escale, service de MPR pédiatrique, hôpital Femme-Mère-Enfant, hospices civils de Lyon, 59, boulevard Pinel, 69677 Bron cedex, France; Université de Lyon, 69000 Lyon, France; Université Lyon-I, 69100 Villeurbanne, France; CNRS, UMR 5558, laboratoire de biométrie et biologie évolutive, équipe biostatistique santé, 69310 Pierre-Bénite, France.
Objective:
To develop a classification for neuromuscular disease patients in each of the three motor function domains (D1: standing and transfers; D2: axial and proximal function; D3: distal function).
Materials And Methods:
A draft classification was developed by a study group and then improved by qualitative validation studies (according to the Delphi method) and quantitative validation studies (content validity, criterion validity and inter-rater reliability). A total of 448 patients with genetic neuromuscular diseases participated in the studies.
Results:
On average, it took 6.3minutes to rate a patient. The inter-rater agreement was good when the classification was based on patient observation or an interview with the patient (Cohen's kappa=0.770, 0.690 and 0.642 for NM-Score D1, D2 and D3 domains, respectively). Stronger correlations (according to Spearman's coefficient) with the respective "gold standard" classifications were found for NM-Score D1 (0.86 vs. the Vignos Scale and -0.88 vs. the Motor Function Measure [MFM]-D1) and NM-Score D2 (-0.7 vs. the Brooke Scale and 0.64 vs. MFM D2) than for NM-Score D3 (0.49 vs. the Brooke scale and -0.49 vs. MFM D3).
Discussion/Conclusions:
The NM-Score is a reliable, reproducible outcome measure with value in clinical practice and in clinical research for the description of patients and the constitution of uniform patient groups (in terms of motor function).
