Classification of complex features of febrile seizures: interrater agreement

As part of a prospective study of febrile seizures, three independent pediatric neurologists rated each of 100 febrile seizures for the presence of complex features: focality, long duration (greater than or equal to 10 min), and occurrence of multiple seizures. Seizure descriptions were assembled from all information available in the medical record and from a semistructured interview of a person who had witnessed the seizure. Interrater agreement assessed by kappa indicated excellent agreement with regard to whether the seizures were multiple or prolonged (kappa greater than or equal to 0.85) and fair to good agreement with regard to focality (kappa = 0.61-0.78). Disagreement occurred most often regarding assessment of focality. Reasons for disagreement included variation in interpretation of lateral eye deviation, staring episodes, and motor asymmetries in the context of a bilateral convulsion.