Classification of childhood epilepsy syndromes in newly diagnosed epilepsy: Interrater agreement and reasons for disagreement

Purpose: The International League Against Epilepsy (ILAE) classification of the epilepsies is in increasingly widespread use. The following analysis w as done to assess the interrater agreement in classifying epilepsy syndrome s in children with newly diagnosed epilepsy. Methods: In a prospective, community-based study, 613 children with newly d iagnosed epilepsy were recruited. Based on information available at diagnos is or generated as part of the initial diagnostic assessment, thr ee pediat ric neurologists independently classified epilepsy syndromes. Interrater ag reement was assessed with kappa. Results: Interrater agreement was extremely good, with kappa scores greater than or equal to 0.80 for almost all comparisons. Relatively limited quali ty of the EEG and seizure information in some cases, as well as discrepanci es between the two, were associated with a tendency for more disagreement. Conclusions: A high degree of interrater agreement was obtained in this stu dy, indicating that the system for classifying syndromes can be meaningfull y used in a community-based sample. Quality of the information, which is of ten, by necessity, less than optimal in newly diagnosed epilepsy, is a pote ntial barrier to identification of syndromes. A substantial proportion of c hildren were classified into relatively nonspecific syndromes. Over time, a dditional information may come to light to allow more precise identificatio n of their forms of epilepsy. In an epidemiologic setting, the ILAE classif ication of the epilepsies can be successfully used with a high degree of re liability to classify newly diagnosed epilepsy in children.