Responders, nonresponders, and placebo responders among children with attention deficit disorder. Importance of a blinded placebo evaluation

Abstract

The responses to methylphenidate of 118 children with attention deficit disorder (ADD) were studied under double-blind conditions. Three distinct types of response to medication and placebo were found, as determined by teacher ratings. One group, called "responders," improved dramatically in attention and hyperactivity ratings on active medication but showed essentially no change from baseline when on placebo. The group called "nonresponders" showed minimal change in ratings on either placebo or medication. The third group, "placebo responders," showed almost as much improvement as the responders on medication, but their ratings were not very different from medication ratings during the placebo trial. The placebo responders, 18 percent of the group, would have been considered responders in a nonplacebo-controlled study. Double-blind placebo evaluation of ADD children can and should be done by practitioners to avoid medicating children who are responding to nonspecific effects of drugs.