The outcome of 131 children with ADHD (101 males, 30 females; mean age 5 years, range 3 to 7 years) with and without oppositional defiant disorder (ODD) was determined in a prospective study at the University of Goteborg, Sweden. Full DSM-IV criteria for ODD were present in 60% of ADHD patients, and only 10 were free of all symptoms of ODD. ADHD combined subtype, males, and children of divorced parents and of mothers with low socioeconomic status were particularly at risk of ODD. ADHD patients with ODD showed more ADHD symptoms than those without ODD. 
COMMENT. The prevalence of association of ADHD and ODD indicates the importance of inclusion of work-up for both disorders in children presenting with either diagnosis.
Prevention of severe learning disability reviewed by O’Brien G  emphasizes the detection and early treatment of comorbid autism and ADHD.