"Your Child Should Not Return": Preschool Expulsion Among Children With Attention-Deficit/Hyperactivity Disorder as an Early Indicator of Later Risks.

Among children ever diagnosed with ADHD, history of preschool expulsion was associated with more severe ADHD symptoms, other disorders, earlier diagnosis and medication initiation, and academic and social impairment. Health care providers can use preschool expulsion as an indicator of risk for children with ADHD and connect families to effective treatments.