This study compared the pretreatment characteristics and posttreatment outc
omes of substance-abusing adolescents with and without comorbid mental diso
rders in the Drug Abuse Treatment Outcome Studies for Adolescents. Subjects
(N = 992) were sampled from 23 adolescent drug treatment programs across t
hree modalities (residential, short-term inpatient, outpatient drug-free).
Nearly two thirds (64%) of the sample had at least one comorbid mental diso
rder, most often conduct disorder. Comorbid youth were more likely to be dr
ug or alcohol dependent and had more problems with family, school, and crim
inal involvement. Although comorbid youth reduced their drug use and other
problem behaviors after treatment, they were more likely to use marijuana a
nd hallucinogens, and to engage in illegal acts in the 12 months after trea
tment, as compared with the noncomorbid adolescents. Integrated treatment p
rotocols need to be implemented within drug treatment programs in order to
improve the outcomes of adolescents with comorbid substance use and mental
disorders.