The Inter-rater Variability of Clinical Assessment in Post-anoxic Myoclonus

Jonathan C van Zijl; Martijn Beudel; Jan-Willem J Elting; Bauke M de Jong; Joukje van der Naalt; Walter M van den Bergh; Andrea O Rossetti; Marina A J Tijssen; Janneke Horn

doi:10.7916/D81R6XBV

The Inter-rater Variability of Clinical Assessment in Post-anoxic Myoclonus

Tremor Other Hyperkinet Mov (N Y). 2017 Jul 13:7:470. doi: 10.7916/D81R6XBV. eCollection 2017.

Authors

Jonathan C van Zijl¹, Martijn Beudel¹, Jan-Willem J Elting^{1

2}, Bauke M de Jong¹, Joukje van der Naalt¹, Walter M van den Bergh³, Andrea O Rossetti⁴, Marina A J Tijssen¹, Janneke Horn⁵

Affiliations

¹ Department of Neurology, University Medical Center Groningen (UMCG), University of Groningen, Groningen, The Netherlands.
² Department of Clinical Neurophysiology, University Medical Center Groningen (UMCG), University of Groningen, Groningen, The Netherlands.
³ Intensive Care Medicine, University Medical Center Groningen (UMCG), University of Groningen, Groningen, The Netherlands.
⁴ Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland.
⁵ Intensive Care Medicine, Amsterdam Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands.

Abstract

Background: Acute post-anoxic myoclonus (PAM) can be divided into an unfavorable (generalized/subcortical) and more favorable ((multi)focal/cortical) outcome group that could support prognostication in post-anoxic encephalopathy; however, the inter-rater variability of clinically assessing these PAM subtypes is unknown.

Methods: We prospectively examined PAM patients using a standardized video protocol. Videos were rated by three neurologists who classified PAM phenotype (generalized/(multi)focal), stimulus sensitivity, localization (proximal/distal/both), and severity (Clinical Global Impression-Severity Scale (CGI-S) and Unified Myoclonus Rating Scale (UMRS)).

Results: Poor inter-rater agreement was found for phenotype and stimulus sensitivity (κ=-0.05), moderate agreement for localization (κ=0.46). Substantial agreement was obtained for the CGI-S (intraclass correlation coefficient (ICC)=0.64) and almost perfect agreement for the UMRS (ICC=0.82).

Discussion: Clinical assessment of PAM is not reproducible between physicians, and should therefore not be used for prognostication. PAM severity measured by the UMRS appears to be reliable; however, the relation between PAM severity and outcome is unknown.

Keywords: Myoclonus; clinical neurology examination; critical care; post-anoxic encephalopathy; prognosis.

Publication types

Multicenter Study
Video-Audio Media
Research Support, Non-U.S. Gov't

MeSH terms

Female
Humans
Hypoxia, Brain / complications*
Hypoxia, Brain / diagnosis
Hypoxia, Brain / physiopathology
Male
Middle Aged
Myoclonus / diagnosis*
Myoclonus / drug therapy
Myoclonus / etiology*
Myoclonus / physiopathology
Neurologic Examination
Neurologists
Observer Variation
Phenotype
Physical Stimulation
Prospective Studies
Reproducibility of Results
Severity of Illness Index
Video Recording