Aggressiveness and explosiveness characterize a subgroup of children d
iagnosed with conduct disorder (CD). Few double-blind, placebo-control
led studies have been conducted in aggressive children with CD, and no
study has differentiated placebo responders from nonresponders. This
study examined factors that may differentiate placebo responders from
nonresponders hospitalized in a structured setting. The sample consist
ed of 25 children, ages 6.25 to 11.95 years, with CD and a profile of
aggressive and explosive behavior who were assigned to placebo treatme
nt as part of a double-blind study of lithium. Responders were compare
d to nonresponders with respect to a detrimental psychosocial environm
ental score, age, IQ, and baseline ratings on the Children's Psychiatr
ic Rating Scale and Clinical Global Impressions. Responders had signif
icantly higher detrimental psychosocial environmental scores than nonr
esponders; they were particularly more likely to come from violent hom
es and to have criminally charged parents. Demographic variables did n
ot distinguish the two groups; however, even mild hyperactivity was as
sociated with poorer response to placebo.