Unsatisfactory Accuracy and Inconsistent Inter-Rater Reliability Among Electroencephalographers in Identifying...

Area of Science:

• Neurology
• Clinical Neurophysiology

Background:

• Epileptic spasms (ES) are a critical diagnosis in epilepsy.
• Accurate identification of ES is often assumed but requires verification, especially for subtle presentations like facial movements.

Purpose of the Study:

• To evaluate the accuracy and inter-rater reliability of experienced electroencephalographers in identifying epileptic spasms (ES) from EEG data.
• To assess the consistency of ES diagnosis among specialists.

Main Methods:

• Six senior electroencephalographers reviewed EEG data from 22 patients diagnosed with ES.
• Evaluators judged the presence or absence of ES in full examinations and 4-second segments.
• Inter-rater reliability (IRR) was quantified using the Fleiss kappa statistic.

Main Results:

• Evaluator accuracy for identifying patients with ES ranged from 0.727 to 0.90.
• Overall IRR was moderate (kappa=0.45), with lower agreement among non-tertiary centers.
• IRR improved significantly for 4-second segments, showing good agreement (kappa=0.63).

Conclusions:

• Significant omissions in ES identification occurred among electroencephalographers.
• Inter-rater reliability for ES diagnosis was unsatisfactory, indicating diagnostic challenges.
• Even experienced specialists find identifying subtle ES difficult.