The number of diagnosed cases of attention-deficit/hyperactivity disorder (ADHD) have increased significantly among adults in the United States within the past decade, which could be due to many factors, including overdiagnosis. A recent JAMA study found that diagnoses of ADHD in adults are growing four times faster than in children. Other research tells another story: that clinicians misdiagnose or miss ADHD in adults and that fewer than 20% of individuals with ADHD are diagnosed and treated by clinicians.