Comparison of a Self-Administered and Physician-Administered Expanded Disability Status Scale with Functional System Scores in Patients with Multiple Sclerosis.

Background: A self-administered Expanded Disability Status Scale (EDSS-S) was developed to measure disability in a large cohort of multiple sclerosis (MS) patients. Methods: Consecutive outpatients with clinically definite MS completed an EDSS-S and a physician-administered EDSS (EDSS-P) during a single visit. If needed, caregivers or clinic staff could assist in completing the form. The EDSS-P visual acuity was obtained using a Snellen chart at 20 feet; gait was actually observed. The EDSS was calculated two ways, using gait and functional system scores (FSS) combined (using a weighted visions FSS) and using gait alone. Results: EDSS-P scores ranged from 0-9.5 (mean 5.1, median 5.0, N=95, 78% female, age 17-78 mean 45). Mean physician-administered scores, patient-administered scores and intraclass correlation coefficients of agreement were: EDSS using ambulation alone (4.6, 5.3, 0.89), EDSS using ambulation + FSS (4.6, 5.3, 0.87), bowel/bladder FSS (1.6, 1.7, 0.79), cerebellar FS (1.1, 1.6, 0.55), brainstem FS (0.5, 1.2, 0.45), vision FS (1.9, 1.3, 0.38), cerebral FS (0.6, 2.3, 0.27). Conclusion: Good correlations were seen between overall EDSS-S and EDSS-P scores. Patients scored themselves more disabled than physicians on most measures.