Symptoms of autism spectrum disorder in subtypes of attention-deficit/hyperactivity disorder

Background This study aimed to compare symptoms of autism spectrum disorder (ASD) in children according to attention-deficit/hyperactivity disorder (ADHD) subtypes and children without ADHD. Method The Schedule for Affective Disorders and Schizophrenia for School-Age Children - Present and Lifetime Version (K-SADS-PL), the Social Responsiveness Scale (SRS), the Childhood Behavior Checklist (CBCL), and the ADHD Rating Scale (ADHD-RS) were used to evaluate the children. Results ASD symptoms were significantly higher in all ADHD subtypes. After controlling for age, gender, and CBCL social withdrawal score, the difference in ASD symptoms between the 3 ADHD subtypes was not significant. Conclusions Children with ADHD, regardless of subtype, had a similar risk of ASD symptoms.