Objective: To clarify the developmental risk associated with hyperactive behavior, especially the relationship between hyperactive and conduct problems, in a longitudinal epidemiological design.
Method: A follow-up study of children who were identified, by parent and teacher ratings in a large community survey of 6- and 7-year-olds, as showing pervasive hyperactivity or conduct problems or the comorbid mixture of both problems or neither problem. They were later investigated, at the age of 16 to 18 years, with detailed interview techniques as well as parental and self-report ratings and cognitive tests.
Results: Hyperactivity was a risk factor for later development, even allowing for the coexistence of conduct problems. Its sequelae included a high likelihood of psychiatric diagnosis, persisting hyperactivity, violence and other antisocial behaviors, and social and peer problems.
Conclusions: The results suggested a developmental pathway through which hyperactivity raised the likelihood of impaired social adjustment, including the development of psychiatric disorders, independently of the existence of conduct problems.