Predictive value of placebo methylphenidate.

The effects of methylphenidate in 20 children with attention-deficit disorder between the ages of 7 and 12 years were assessed in a double-blind, placebo/drug counterbalanced study. Measures of outcome included the Teacher Rating Scale and Abbreviated Parent Rating Scale: digits, words, and visual sequencing; motor control; and a maze test. The Teacher Rating Scale placebo-drug difference correlated more significantly with the outcome measures than the baseline-drug difference. The study underlines the validity of a multimeasure placebo/drug trial in evaluating the efficacy of methylphenidate in children with attention-deficit disorder.