Validation of the Charcot–Marie–Tooth disease pediatric scale as an outcome measure of disability
Article first published online: 20 APR 2012
Copyright © 2012 American Neurological Association
Annals of Neurology
Volume 71, Issue 5, pages 642–652, May 2012
How to Cite
Burns, J., Ouvrier, R., Estilow, T., Shy, R., Laurá, M., Pallant, J. F., Lek, M., Muntoni, F., Reilly, M. M., Pareyson, D., Acsadi, G., Shy, M. E. and Finkel, R. S. (2012), Validation of the Charcot–Marie–Tooth disease pediatric scale as an outcome measure of disability. Ann Neurol., 71: 642–652. doi: 10.1002/ana.23572
- Issue published online: 20 APR 2012
- Article first published online: 20 APR 2012
- Accepted manuscript online: 28 FEB 2012 11:05PM EST
- Manuscript Accepted: 10 FEB 2012
- Manuscript Revised: 15 JAN 2012
- Manuscript Received: 21 SEP 2011
- National Health and Medical Research Council of Australia. Grant Number: #1007569
- NIH National Institutes of Neurological Disorders and Stroke and Office of Rare Diseases. Grant Number: #U54NS065712
- Charcot Marie Tooth Association, Muscular Dystrophy Association, and CMT Association of Australia
Charcot–Marie–Tooth disease (CMT) is a common heritable peripheral neuropathy. There is no treatment for any form of CMT, although clinical trials are increasingly occurring. Patients usually develop symptoms during the first 2 decades of life, but there are no established outcome measures of disease severity or response to treatment. We identified a set of items that represent a range of impairment levels and conducted a series of validation studies to build a patient-centered multi-item rating scale of disability for children with CMT.
As part of the Inherited Neuropathies Consortium, patients aged 3 to 20 years with a variety of CMT types were recruited from the USA, United Kingdom, Italy, and Australia. Initial development stages involved definition of the construct, item pool generation, peer review, and pilot testing. Based on data from 172 patients, a series of validation studies were conducted, including item and factor analysis, reliability testing, Rasch modeling, and sensitivity analysis.
Seven areas for measurement were identified (strength, dexterity, sensation, gait, balance, power, endurance), and a psychometrically robust 11-item scale was constructed (CMT Pediatric Scale [CMTPedS]). Rasch analysis supported the viability of the CMTPedS as a unidimensional measure of disability in children with CMT. It showed good overall model fit, no evidence of misfitting items, and no person misfit, and it was well targeted for children with CMT.
The CMTPedS is a well-tolerated outcome measure that can be completed in 25 minutes. It is a reliable, valid, and sensitive global measure of disability for children with CMT from the age of 3 years. ANN NEUROL 2012;