A trial of proficiency of nerve conduction: Greater standardization still needed


  • This article includes Supplementary Material available via the internet at http://www.mrw.interscience.wiley.com/suppmat/0148-639X/suppmat/

  • This study was supported by Mayo Foundation funds with grants obtained from the National Institute of Neurological Disorders and Stroke (NS36797 to P.J.D.), and by the National Institute on Aging of the National Institutes of Health (R01AGO34676).

  • Disclosure: The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Correspondence to: P.J. Dyck; e-mail: dyck.peter@mayo.edu



The aim of this study was to test the proficiency (accuracy among evaluators) of measured attributes of nerve conduction (NC).


Expert clinical neurophysiologists, without instruction or consensus development, from 4 different medical centers, independently assessed 8 attributes of NC in 24 patients with diabetes mellitus (DM) on consecutive days.


No significant intraobserver differences between days 1 and 2 were found, but significant interobserver differences were seen. Use of standard reference values did not correct for these observed differences.


Interobserver variability was attributed to differences in performance of NC. It was of sufficient magnitude that it is of concern for the conduct of therapeutic trials. To deal with interrater variability in therapeutic trials, the same electromyographers should perform all NC assessments of individual patients or, preferably, NC procedures should be more standardized. A further trial is needed to test whether such standardization would eliminate interobserver variability. Muscle Nerve 48: 369–374, 2013