Self-administered Expanded Disability Status Scale with functional system scores correlates well with a physician-administered test

Abstract

Background: Patient-administered measures are needed to assess disability cost-effectively in large epidemiological studies.

Setting: An outpatient clinic in a large multiple sclerosis center.

Methods: A self-administered EDSS questionnaire was developed (EDSS-S). Consecutive patients with clinically definite multiple sclerosis completed the EDSS-S (n=95). During the same visit, a physician completed an EDSS (EDSS-P). Scores below 4.0 were determined using functional system (FS) scores. Scores above 4.0 were calculated by two methods, using gait alone and using gait and functional system scores combined.

Results: EDSS-P scores ranged from 0-9.5 (mean 5.1, median 5.0, 78% female, age 17-78, mean age 45). Mean EDSS-P, EDSS-S and intraclass correlation coefficients of agreement were: EDSS using ambulation alone (4.6, 5.1, 0.89), EDSS using ambulation and FS scores (4.6, 5.3, 0.87), bowel/bladder FS scores (1.6, 1.7, 0.79), pyramidal FS scores (2.1, 2.4, 0.67), sensory FS scores (1.6, 2.1, 0.60), cerebellar FS scores (1.1, 1.6, 0.55), brainstem FS scores (0.5, 1.2, 0.45), vision FS scores (1.9, 1.3, 0.38), cerebral FS scores (0.6, 2.3, 0.27).

Conclusions: Very good correlation was seen between patient and physician scores for EDSS and the bowel/bladder FS score. Four other FS scores correlated moderately. In general, patients scored themselves more disabled than physicians.