Objective: Although methylphenidate and atomoxetine have positive effects in reducing core symptoms and emotional/behavioral problems of attention-deficit/hyperactivity disorder (ADHD), little is known about their efficacy in improving social adjustment problems among youths with ADHD. Methods: A total of 168 drug-naive youths, 7-16 years of age, with DSM-IV-defined ADHD, were recruited and randomly assigned to osmotic-release oral system methylphenidate (n = 83) and atomoxetine (n = 85) in a 24-week, open-label, head-to-head clinical trial. Efficacy measurement was based on the parent-rated and self-rated Social Adjustment Inventory for Children and Adolescents (SAICA). Evaluation time points were set at baseline and weeks 8, 16, and 24. Results: At week 24, methylphenidate was associated with improvement in school functions (parent report: Cohen d = -0.82; self-report: Cohen d = -0.66) and peer relationships (parent report: Cohen d = -0.50; self-report: Cohen d = -0.25); and atomoxetine was associated with improvement in school functions (parent report: Cohen d = -0.62; self-report: Cohen d = -0.34) and peer relationships (parent report: Cohen d = -0.33; self-report: Cohen d = -0.65). In terms of parent-reported and self-reported ratings, there were no significant differences between the two treatment groups in mean reduction in the severity of school dysfunctions, impaired peer relationships, and behavioral problems at home at week 24. Conclusions: Our findings lend evidence to support that both methylphenidate and atomoxetine were comparably effective in improving social adjustment in youths with ADHD, including school functions and peer relationships.
Keywords: atomoxetine; attention-deficit/hyperactivity disorder; clinical trial; methylphenidate; social adjustment.