Prevalence of epilepsy in children.

UMMARY A questionnaire survey for epilepsy was mailed to 2042 families of third-grade students in Washington County, Md. The final 1866 responses were stratified into 8 groups. It was hypothesized that the percentage of children with epilepsy in Groups 1–3 would be significantly higher than in Groups 4–7. A sample of 200 children was selected for clinical and EEG examination to test this hypothesis and to validate the questionnaire. Of children examined in Group 1, 53% had epilepsy; in Groups 2–3, 8% had epilepsy, in Group 4, 2% had epilepsy. No cases of epilepsy were found in children from Groups 5–7. To develop a comprehensive prevalence estimate for epilepsy, 6 institutions were surveyed by telephone. A minimum prevalence rate of 14.1 per 1000 was derived by adding the cases of epilepsy in the institutionalized group to those found in the questionnaire survey, and dividing by the population at risk. A more reasonable prevalence rate of 18.6 per 1000 was derived by assuming that those not examined in each questionnaire group would have the same rate of epilepsy as those examined. A maximum prevalence rate of 20.1 per 1000 was derived by assuming that non-respondents to the questionnaire would have the same rate of epilepsy as respondents. Prevalence rates for simple febrile convulsions and minimal brain dysfunction were similarly calculated. ABSTRACT A questionnaire was developed to ascertain the prevalence of epilepsy in a population of about 2000 third-grade students. Samples were examined clinically and by EEG, and institutions were surveyed. The prevalence rate was 18.6–20.1/1000 (calculated reasonable and maximum rates). The corresponding rates for “simple febrile convulsions” were 48 and 52.5/1000, and for minimal brain dysfunction 18.6 and 20.4/1000. Distinction between the various types of epilepsy was not highly reliable by the questionnaire in its present form. RESUME Un questionnaire a ete developpe pour s'assurer de la prevalence de ľepilepsie dans une population ďenviron 2000 etudiants du troisieme grade. Des echantillons ont eteetudies cliniquement et par ľelectroencephalographie et des instituts ont ete examines. Le taux de prevalence etait de 18.6–20.1/1000 (taux calcules raisonnables et maximales). Le taux correspondant a de simples convulsions febriles etait de 48 et 52.5/1000 et celui correspondant a une dysfonction cerebrate mineure etait de 18.6 et 20.4/1000. La distinction entre les differents types ďepilepsies n'etait pas largement pas reliable au questionnaire redige dans cette forme-la. ZUSAMMENFASSUNG Ein Fragebogen wurde entwickelt, um die Haufigkeit der Epilepsie unter 1866 Schulern der dritten Klasse zu ermitteln. Stichproben wurden klinisch und mit EEG untersucht, und Institutionen begutachtet. Die Verbreitungshaufigkeit betrug 18.6 bis 20.1 je 1000 (errechnete Wahrscheinlichkeits- und Maximalwerte). Die ensprechenden Zahlen fur einfache febrile Krampfe waren 48 und 52.5 je 1000, fur minimale Hirnfunktionsstorungen 18.6 und 20.4 je 1000. Um eine unterschiedliche Beteiligung der verschiedenen Typen der Epilepsie aufzudecken, war der Fragebogen in der gegenwartigen Form nicht sehr ergiebig. RESUMEN Se ha utilizado un cuestionario para averiguar la importancia de la epilepsia en una poblacion de 2000 estudiantes de tercer grado. Muestras variables de diferentes instituciones han sido examinadas desde el punto de vista clinico y EEG. Los porcentajes observados eran entre el 18.6 y el 20.1/1.000. Los porcentajes correspondientes refererntes a “simples convulsiones febriles” eran de 48–52.5/1.000 y para los casos de disfuncion cerebral minima de 18.6 y 20.4/1.000. Las dos cifras citadas para cada uno de los porcentajes corresponden a la civra promedio y maxima de cada grupo. En la forma actual en que se ha llevado a cabo la investigacion no es posible establecer proporciones entre los diferentes tipos de epilepsia.