MS-CANE: a computer-aided instrument for neurological evaluation of patients with multiple sclerosis: enhanced reliability of expanded disability status scale (EDSS) assessment

Kurtzke's EDSS remains the most widely-used measure for clinical evaluation of MS patients. However, several studies have demonstrated the limited rel iability of this tool. We introduce a computerized instrument, MS-CANE (Mul tiple Sclerosis Computer-Aided Neurological Examination), for clinical eval uation and follow up of patients with multiple sclerosis (MS) and to compar e its reliability to that of conventional Expanded Disability Status Scale (EDSS) assessment We developed a computerized interactive instrument based on the following principles: structured gathering of neurological findings, reduction of compound notions to their basic components use of precise def initions priority setting and automated calculations of EDSS and functional systems scores. An expert panel examined the consistency of MS-CANE with K urtzke's specifications. To determine the effect of MS-CANE on the reliabil ity of EDSS assessment, 56 MS patients underwent paired conventional EDSS a nd MS-CANE-based evaluations. The inter-observer agreement in both methods was determined and compared using the kappa statistic The expert panel judg ed the tool to be compatible with the basic concepts of Kurtzke's EDSS. The use of MS-CANE increased the reliability of EDSS assessment Kappa statisti c was found to be 0.42 (i.e. moderate agreement) for conventional EDSS asse ssment versus 0.69 (i.e. substantial agreement) for MS-CANE (P=0.002). We c onclude that the use of this tool may contribute towards a standardized and reliable assessment of EDSS. Within clinical trials this could increase th e power to detect effects, thus reducing trial duration and the cohort size required.