Prevalence of hyperactivity in elementary school children as a function of social system definers.

This study seeks to reconcile the widely varying estimates of prevalence of hyperactivity in children. Parents, teachers, and physicians were asked to identify hyperactive children in a sample of some 5000 elementary school children. Approximately five percent were considered hyperactive by at least one defining system; only one percent were considered hyperactive by all three definers. Prevalence rates were relatively constant from kindergarten through fifth grade.