Development and validation of a motor function classification in patients with neuromuscular disease: the NM-score.
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).


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).


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).
L'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. Electronic address: carole.vuillerot@gmail.com.
C
C
Vuillerot
P
P
Rippert
S
S
Roche
C
C
Bérard
F
F
Margirier
C
C
de Lattre
I
I
Poirot
A
A
Berruyer
V
V
Tiffreau
M
M
Fournier-Mehouas
F
F
Bouhour
J-A
JA
Urtizberea
A
A
Renders
R
R
Ecochard
D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000145:classification*; D009068:Movement; D009468:Neuromuscular Diseases / Q000503:physiopathology*; D015588:Observer Variation; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013997:Time Factors; D055815:Young Adult
Activities of daily living; Activités de la vie quotidienne; Fonction motrice; Maladies neuromusculaires; Motor function; Neuromuscular disease; Outcome measure; Évaluation