To the Editor.—
In a recent article in the Archives (35:17-21, 1978), Ellenberg and Nelson found no difference in later intellectual performance between children who had had febrile seizures and their seizure free siblings. On this basis, they claim that "febrile seizures, initial or recurrent, are not likely to cost the child a measurable decrement in intelligence or early academic achievement."We are not convinced that this claim may really be derived from their data. In fact, a group of patients with febrile convulsions had, according to the authors' own data, an unfavorable mental outcome: those in whom afebrile seizures developed after febrile fits. Of 52 infants in this group, 14 (27%) at least were neurologically and/or mentally abnormal.1 Excluding these patients from analysis necessarily leads to an optimistic result that applies only to infants without afebrile seizures.It is not possible, however, to know beforehand in which particular