A four-year follow-up study of the effects of methylphenidate on the behavior and academic achievement of hyperactive children.

Sixty-two children were evaluated 4 years after their initial referral for symptoms of hyperactivity. Behavioral measures included parent and teacher judgments of behavior and social adjustment. Academic achievement was assessed by teachers' reports, number of failed grades, special education services, and two individually administered achievement tests. Data were analyzed for the total group to determine both the extent to which presenting problems diminished over time and the major problems still present. The effects of stimulant drug therapy on outcome were assessed by dividing the children into groups according to the duration of time they had taken stimulants. Total duration of time on stimulants ranged from less than 6 months (group 1) to 4 years (group 5). Results indicated that the symptoms of hyperactivity significantly lessened, but remained higher in these children than in normal peers. Behavioral and social problems were less pervasive than academic underachievement. There were no group differences, indicating that the duration of stimulant intervention did not have a significant effect on outcome. The clinical implication of this study is that the beneficial effects of stimulant drug intervention occur within the first months after initiation of therapy. Long-term treatment does not appear to be of value in producing better outcome.