Inter and intra-observer reliability in Kurtzke scoring systems in multiple sclerosis

Area of Science:

• Neurology
• Clinical Assessment
• Multiple Sclerosis Research

Background:

• The Kurtzke Expanded Disability Status Scale (EDSS) is a widely used tool for assessing neurological disability in Multiple Sclerosis (MS).
• Evaluating the reliability of the EDSS is crucial for consistent clinical practice and research, especially in international comparisons.
• Variability in scoring can impact patient management and trial outcomes.

Purpose of the Study:

• To assess the inter- and intra-observer variability of the Kurtzke EDSS in patients with definite Multiple Sclerosis.
• To compare the reliability of the original Kurtzke EDSS with a modified version used in the Italian Multicenter MS Case-Control Study Group.

Main Methods:

• Seventy patients with definite MS were scored by four independent neurologists.
• Forty patients were assessed using the original Kurtzke EDSS, and 30 using a modified version.
• Inter- and intra-observer agreement was evaluated using the weighted Kappa index after a 1-month interval.

Main Results:

• A high level of concordance was observed for both inter- and intra-observer comparisons across all items of the Kurtzke EDSS.
• No significant differences in reliability were found between the original and modified Kurtzke EDSS versions.
• The weighted Kappa index indicated substantial agreement among neurologists.

Conclusions:

• The Kurtzke EDSS demonstrates high reliability for assessing neurological status in MS patients.
• Both the original and modified versions of the scale exhibit comparable reliability.
• The findings support the continued use of the Kurtzke EDSS for consistent neurological assessment in MS.