Spring Aaron M, Pittman Daniel J, Aghakhani Yahya, Jirsch Jeffrey, Pillay Neelan, Bello-Espinosa Luis E, Josephson Colin, Federico Paolo
Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family MR Research Centre, Foothills Medical Centre, Calgary, AB, Canada.
Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family MR Research Centre, Foothills Medical Centre, Calgary, AB, Canada.
Clin Neurophysiol. 2017 Mar;128(3):433-441. doi: 10.1016/j.clinph.2016.12.017. Epub 2016 Dec 30.
High frequency oscillations (HFOs) and interictal epileptiform discharges (IEDs) have been shown to be markers of epileptogenic regions. However, there is currently no 'gold standard' for identifying HFOs. Accordingly, we aimed to formally characterize the interrater reliability of HFO markings to validate the current practices.
A morphology detector was implemented to detect events (candidate HFOs, lower-threshold events, and distractors) from the intracranial EEG (iEEG) of ten patients. Six electroencephalographers visually evaluated these events for the presence of HFOs and IEDs. Interrater reliability was calculated using pairwise Cohen's Kappa (κ) and intraclass correlation coefficients (ICC).
The HFO evaluation distributions were significantly different for most pairs of reviewers (p<0.05; 11/15 pairs). Interrater reliability was poor for HFOs alone (κ=0.403; ICC=0.401) and HFO+IEDs (κ=0.568; ICC=0.570).
The current practice of using two visual reviewers to identify HFOs is prone to bias arising from the poor agreement between reviewers, limiting the extrinsic validity of studies using these markers.
The poor interrater reliability underlines the need for a framework to reconcile the important findings of existing studies. The present epoched design is an ideal candidate for the implementation of such a framework.
高频振荡（HFOs）和发作间期癫痫样放电（IEDs）已被证明是致痫区域的标志物。然而，目前尚无识别HFOs的“金标准”。因此，我们旨在正式描述HFO标记的评分者间可靠性，以验证当前的做法。
采用一种形态检测器从10例患者的颅内脑电图（iEEG）中检测事件（候选HFOs、低阈值事件和干扰物）。6名脑电图专家对这些事件进行视觉评估，以确定是否存在HFOs和IEDs。使用配对Cohen's Kappa（κ）和组内相关系数（ICC）计算评分者间可靠性。
大多数评审员对之间的HFO评估分布存在显著差异（p<0.05；11/15对）。单独的HFOs（κ=0.403；ICC=0.401）和HFO+IEDs（κ=0.568；ICC=0.570）的评分者间可靠性较差。
目前使用两名视觉评审员识别HFOs的做法容易因评审员之间的一致性差而产生偏差，限制了使用这些标志物的研究的外部有效性。
评分者间可靠性差凸显了需要一个框架来协调现有研究的重要发现。目前的分段设计是实施这样一个框架的理想候选方案。
