The effect of methylphenidate on school grades in children with attention deficit disorder without hyperactivity: a preliminary report.

Ten children, aged 7-12 years, were diagnosed by DSM-III criteria for attention deficit disorder (ADD) without hyperactivity. Each child was treated with methylphenidate for one academic grading period. School grades were obtained for the grading periods before, during, and after drug treatment. Correlated t tests revealed that academic performance during drug treatment was significantly superior to that during the preceding grading period (p less than .01) and the period following drug treatment (p less than .001). ADD without hyperactivity may represent a potentially drug-treatable disorder in children.