Deriving reference values in electrodiagnostic medicine

✍ Scribed by Dr. William W. Campbell; Dr. Lawrence R. Robinson

• Book ID: 102535005
• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 475 KB
• Volume: 16
• Category: Article
• ISSN: 0148-639X
• DOI: 10.1002/mus.880160414

✦ Synopsis

Abstract

Traditional methods for determining nerve conduction reference values have usually involved studying a group of normal controls, and determining the mean ± 2 standard deviations (SD) for each parameter. Recent studies suggest other factors should be taken into account. Height has a greater effect on conduction velocity than age or temperature. The common assumption that conduction values follow a normal, bell‐shaped Gaussian distribution appears unwarranted. The curve for some conduction parameters is significantly skewed, making a mean ± 2 SD definition of normality inaccurate to a clinically important degree. In developing and using reference values one should consider height, age, and temperature, and calculate the mean ± 2 SD of the transformed data to remove the effects of skew. Reference values provide only a guide to the probability a given result came from a healthy or diseased individual; one should therefore seek multiple internally consistent abnormalities before diagnosing disease on the basis of electroneurography. © 1993 John Wiley & Sons, Inc.