In some parts of the world, the number of girls diagnosed with attention-deficit/hyperactivity disorder is surpassing boys, according to new research − a trend we've not yet seen in the United States. In the study, published April 8 in JAMA, researchers found ADHD diagnoses in post-pandemic years among female adolescents and young adults in British Columbia, Canada surpassed same-aged males for the first time on record. High school-aged adolescents were defined as ages 13 to 17 and young adults as 18 to 29. The study analyzed British Columbia health data from more than 2.7 million patients aged 3 to 29 from 2003 to 2023.