Smith, Benn

ABSTRACT Introduction: There are not uniform standards for nerve conduction testing across the United States. The objective of this study is to present a set of methodologically sound criteria to evaluate the literature for the purpose of identifying high‐quality normative nerve conduction studies (NCS) suitable for widespread use. Methods: The Normative Data Task Force (NDTF) was formed to review published studies on methodological issues related to NCS. A set of criteria was then developed to evaluate the literature. These criteria and their rationale are described. Results: We identified 7 key issues that reflect high quality in NCS. For each issue, specific review criteria were developed. Conclusion: Rigorous criteria enable identification of high‐quality studies dealing with nerve conduction reference values. This represents the first step toward the overarching goal of recommending NCS techniques and reference values for electrodiagnostic medicine. Muscle Nerve 54 : 366–370, 2016

ABSTRACT Introduction: To address the need for greater standardization within the field of electrodiagnostic medicine, the Normative Data Task Force (NDTF) was formed to identify nerve conduction studies (NCS) in the literature, evaluate them using consensus‐based methodological criteria derived by the NDTF, and identify those suitable as a resource for NCS metrics. Methods: A comprehensive literature search was conducted of published peer‐reviewed scientific articles for 11 routinely performed sensory and motor NCS from 1990 to 2012. Results : Over 7,500 articles were found. After review using consensus‐based methodological criteria, only 1 study each met all quality criteria for 10 nerves. Conclusion: The NDTF selected only those studies that met all quality criteria and were considered suitable as a clinical resource for NCS metrics. The literature is, however, limited and these findings should be confirmed by larger, multicenter collaborative efforts. Muscle Nerve 54 : 371–377, 2016

ABSTRACT Introduction: The aim of this study was to create reference values for jitter measured with concentric needle electrodes. Methods: Operators worldwide contributed recordings from orbicularis oculi (OO), frontalis (FR), and extensor digitorum (ED) muscles in healthy controls. Criteria for acceptable signal quality were agreed upon in advance. Fifteen or 20 recordings of acceptable quality from each muscle were required for voluntary and electrical stimulation recordings, respectively. Results: Recordings from 59 to 92 subjects were obtained for each muscle and activation type. Outlier limits for mean consecutive difference and individual jitter data for voluntary activation were: OO, 31 and 45 µs; FR, 28 and 38 µs; ED, 30 and 43 µs; and for electrical stimulation they were: OO, 27 and 36 µs; FR, 21 and 28 µs; ED, 24 and 35 µs. Conclusion: Reference jitter values from concentric needle electrode recordings were developed from signals of defined quality while seeking to avoid creating supernormal values. Muscle Nerve 53: 351–362, 2016