Large inter-rater variability on EEG-reactivity is improved by a novel quantitative method

TY - JOUR

T1 - Large inter-rater variability on EEG-reactivity is improved by a novel quantitative method

AU - Duez, Christophe Henri Valdemar

AU - Ebbesen, Mads Qvist

AU - Benedek, Krisztina

AU - Fabricius, Martin

AU - Atkins, Mary Doreen

AU - Beniczky, Sandor

AU - Kjaer, Troels W

AU - Kirkegaard, Hans

AU - Johnsen, Birger

N1 - Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

PY - 2018/4

Y1 - 2018/4

N2 - OBJECTIVE: To assess inter-rater agreement on EEG-reactivity (EEG-R) in comatose patients and compare it with a quantitative method (QEEG-R).METHODS: Six 30-s stimulation epochs (noxious, visual and auditory) were performed during EEG on 19 neurosurgical and 11 cardiac arrest patients. Six experts analysed EEGs for reactivity using their habitual methods. QEEG-R was defined as present if ≥2/6 epochs were reactive (stimulation/rest power ratio exceeding noise level). Three-months patient outcome was assessed by the Cerebral Performance Category Score (CPC) dichotomized in good (1-2) or poor (3-5).RESULTS: Agreement among experts on overall EEG-R varied from 53% to 83% (κ: 0.05-0.64) and reached 100% (κ: 1) between two QEEG-R calculators. For the experts, absence of EEG-R yielded sensitivities for poor outcome between 40-85% and specificities between 20-90%, for QEEG-R sensitivity was 40% (CI: 23-68%) and specificity 100% (CI: 69-100%).CONCLUSIONS: There is a large inter-rater variation among experts on EEG-R assessment in comatose patients. QEEG-R is a promising objective prognostic parameter with low inter-rater variation and a high specificity for prediction of poor outcome.SIGNIFICANCE: Clinicians should be cautious when using the traditional, qualitative method, in particular in end-of-life decisions. Implementation of the quantitative method in clinical practice may improve reliability of reactivity assessments.

AB - OBJECTIVE: To assess inter-rater agreement on EEG-reactivity (EEG-R) in comatose patients and compare it with a quantitative method (QEEG-R).METHODS: Six 30-s stimulation epochs (noxious, visual and auditory) were performed during EEG on 19 neurosurgical and 11 cardiac arrest patients. Six experts analysed EEGs for reactivity using their habitual methods. QEEG-R was defined as present if ≥2/6 epochs were reactive (stimulation/rest power ratio exceeding noise level). Three-months patient outcome was assessed by the Cerebral Performance Category Score (CPC) dichotomized in good (1-2) or poor (3-5).RESULTS: Agreement among experts on overall EEG-R varied from 53% to 83% (κ: 0.05-0.64) and reached 100% (κ: 1) between two QEEG-R calculators. For the experts, absence of EEG-R yielded sensitivities for poor outcome between 40-85% and specificities between 20-90%, for QEEG-R sensitivity was 40% (CI: 23-68%) and specificity 100% (CI: 69-100%).CONCLUSIONS: There is a large inter-rater variation among experts on EEG-R assessment in comatose patients. QEEG-R is a promising objective prognostic parameter with low inter-rater variation and a high specificity for prediction of poor outcome.SIGNIFICANCE: Clinicians should be cautious when using the traditional, qualitative method, in particular in end-of-life decisions. Implementation of the quantitative method in clinical practice may improve reliability of reactivity assessments.

KW - Coma prognosis

KW - EEG reactivity

KW - Inter-rater variation

KW - Outcome prediction

KW - Quantitative EEG

UR - http://www.scopus.com/inward/record.url?scp=85041795508&partnerID=8YFLogxK

U2 - 10.1016/j.clinph.2018.01.054

DO - 10.1016/j.clinph.2018.01.054

M3 - Journal article

C2 - 29448148

SN - 1388-2457

VL - 129

SP - 724

EP - 730

JO - Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology

JF - Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology

IS - 4

ER -