Hyperactivity in school-age boys and subsequent risk of injury.

Hyperactive boys between 6 and 8 years of age, identified through systematic population-based screening of a community in London, were compared prospectively with a nonhyperactive control group to determine whether they were at greater risk of sustaining injuries. The study sample was drawn from 1296 completed parent and teacher questionnaires. Hyperactive groups were designated in three ways (parental report, teacher report, and combined parent and teacher report). Injuries were assessed by reviewing the medical records of the five emergency departments serving the community. Although boys with conduct problems did sustain more injuries than control subjects, no relationship between hyperactivity and injury was found. Similarly, when milder injuries were excluded from the analysis, the association remained negative. The absence of an association could not be accounted for by differential parental protectiveness of boys designated hyperactive. This study, which has a power of .80 to determine an increase in the relative risk of injury of 1.5, found no effect for hyperactive behavior in boys. Hyperactive behavior is probably not a risk factor for injury; if it is, it exerts a modest effect, less than 1.5, therefore accounting for less than 4% of injuries to school-aged boys.