Differential effects of methylphenidate on attentional functions in children with attention-deficit/hyperactivity disorder.

Objective: To examine the effects of methylphenidate on different attentional functions and behavior in children with attention-deficit/hyperactivity disorder (ADHD).

Method: A total of 60 ADHD children aged between 8 and 12 years completed a randomized, double-blind, placebo-controlled, within-subject crossover trial with two doses of methylphenidate (0.25 and 0.