How Related Are Adult and Childhood ADHD?

Diagnosing attention-deficit/hyperactivity disorder (ADHD) in adults is tricky, especially if clinicians demand prior diagnoses of childhood ADHD. Investigators in New Zealand studied 1037 individuals born in 1972 and 1973 (men, 53%; white, 93%). They were assessed every 2 to 3 years until age 21 and then at ages 26, 32, and 38. For both children and adults, close informants confirmed symptoms.

DSM-III childhood ADHD diagnoses were made through age 15 and required symptom onset before age 7; 61 children (6%) met ADHD criteria. Diagnoses at age 38 were based on a 27-item inventory operationalizing the 18 DSM-5 adult ADHD symptoms; 31 respondents met criteria (3%). Although 70% of diagnosed adults had contact with professionals for mental heal…