Factors related to agreement between self-reported and conventional Expanded Disability Status Scale (EDSS) scores.

Background: Although the Expanded Disability Status Scale (EDSS) remains a widely used scale for evaluating impairments in people with multiple sclerosis (MS), EDSS assessments are infeasible in certain situations. A self-administered version of the EDSS would be potentially usefulif it yielded similar results as the conventional physician-based version. Methods: We developed a self-administered patient questionnaire to obtain ratings of neurologic impairments, and developed algorithms to estimate EDSS scores. We mailed the questionnaires to all new consecutive patients scheduled to be seen at an MS clinic. Questionnaires were completed prior to the visit, and traditional EDSS ratings were made by one of two neurologists at the visit. One hundred and forty-six pairs of patient questionnaires and physician EDSS assessments were obtained. Results: Kappa values for agreement between the physician's EDSS scores and the questionnaire-derived scores were 0.13 (for exact agreement), 0.39 (+0.5 EDSS steps), and 0...