There is a lack of nationally representative studies examining the co-occurrence of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in children. This study examines comorbid mental, behavioral, and developmental disorders (MBDDs) and associated treatment modalities for children with co-occurring ASD and ADHD. Cross-sectional analyses were conducted using data from the pooled 2016-2018 National Survey of Children’s Health (sample n = 102,341). Nationally…