Purpose: We evaluated the validity and interrater reliability of encephalographer interpretation of color density spectral array EEG for seizure identification was evaluated in critically ill children and explored predictors of accurate seizure identification.
Methods: Conventional EEG tracings from 21 consecutive critically ill children were scored for electrographic seizures. Four 2-hour long segments from each subject were converted to 8-channel color density spectral array displays, yielding 84 images. Eight encephalographers received color density spectral array training and circled elements thought to represent seizures. Images were reviewed in random order (Group A) or with information regarding seizure presence in the initial 30 minutes and with subject images in order (Group B). Sensitivity, specificity, and interrater reliability were calculated. Factors associated with color density spectral array seizure identification were assessed.
Results: Seizure prevalence was 43% on conventional EEG. Specificity was significantly higher for Group A than Group B (92.3% vs. 78.2%, P < 0.00). Sensitivity was not significantly different between Groups A and B (64.8% vs. 75%, P = 0.22). Interrater reliability was moderate in both groups. Ten percent of images were falsely classified as containing a seizure. Seizure duration ≥2 minutes predicted identification (P < 0.001).
Conclusions: Color density spectral array may be a useful screening tool for seizure identification by encephalographers, but it does not identify all seizures and false positives occur.