Article

OBJECTIVES: To monitor treatment effects in patients with congenital myopathies
and congenital muscular dystrophies, valid outcome measures are necessary. The
Motor Function Measure (MFM) was examined for robustness, and changes are
proposed for better adequacy. DESIGN: Observational study based on data
previously collected from several cohorts. SETTING: Nineteen departments of
physical medicine or neuromuscular consultation in France, Belgium, and the
United States. PARTICIPANTS: Patients (N=289) aged 5 to 77 years. INTERVENTIONS:
None. MAIN OUTCOME MEASURES: A Rasch analysis examined the robustness of the MFM
across the disease spectrum. The 3 domains of the scale (standing position and
transfers, axial and proximal motor function, and distal motor function) were
independently examined with a partial credit model. RESULTS: The original 32-item
MFM did not sufficiently fit the Rasch model expectations in either of its
domains. Switching from a 4- to a 3-category response scale in 18 items restored
response order in 16. Various additional checks suggested the removal of 7 items.
The resulting Rasch-scaled Motor Function Measure with 25 items for congenital
disorders of the muscle (Rs-MFM25(CDM)) demonstrated a good fit to the Rasch
model. Domain 1 was well targeted to the whole severity spectrum-close mean
locations for items and persons (0 vs 0.316)-whereas domains 2 and 3 were better
targeted to severe cases. The reliability coefficients of the Rs-MFM25(CDM)
suggested sufficient ability for each summed score to distinguish between patient
groups (0.9, 0.8, and 0.7 for domains 1, 2, and 3, respectively). A sufficient
agreement was found between results of the Rasch analysis and physical
therapists' opinions. CONCLUSIONS: The Rs-MFM25(CDM) can be considered a
clinically relevant linear scale in each of its 3 domains and may be soon
reliably used for assessment in congenital disorders of the muscle.
CI - Copyright (c) 2014 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS