Psychometric evaluation of the myasthenia gravis composite using Rasch analysis.

Journal Article (Journal Article)

INTRODUCTION: The MG Composite (MGC) is a validated outcome measure of the clinical manifestations of myasthenia gravis. METHODS: We performed Rasch analyses of the MGC to investigate additional properties, including its unidimensionality and the appropriateness of the weights assigned to the response categories for the MGC items. RESULTS: The fit statistics indicated that the 10 items belong together and can be summated for a total score. There was an overall absence of item order distortion between response categories. The Rasch model's expected category response values were compatible with item weights previously assigned. CONCLUSIONS: Our analysis suggests that: (1) the score can be summated to estimate an overall disease severity score; (2) the response options of the 10 items are not significantly distorted; and (3) the assigned weights of the response options are appropriate.

Full Text

Duke Authors

Cited Authors

  • Sadjadi, R; Conaway, M; Cutter, G; Sanders, DB; Burns, TM; MG Composite MG-QOL15 Study Group,

Published Date

  • June 2012

Published In

Volume / Issue

  • 45 / 6

Start / End Page

  • 820 - 825

PubMed ID

  • 22581534

Electronic International Standard Serial Number (EISSN)

  • 1097-4598

Digital Object Identifier (DOI)

  • 10.1002/mus.23260


  • eng

Conference Location

  • United States