Investigators at the National Institute of Mental Health, Bethesda, MD, compared the prevalence and clinical correlates of DSM-IV-TR versus DSM-5-defined ADHD and subtypes in a nationally representative sample of US youth based on age-of-onset criterion. Extension of the age-of-onset criterion from 7 to 12 years led to an increase in the prevalence rate of ADHD from 7.38% (DSM-IV-TR) to 10.84% (DSM-5). Severity of ADHD and patterns of comorbidity were not changed by the later age-of-onset, but the group with later age of onset was more likely to be from lower income and ethnic minority families. 
COMMENTARY. The DSM-5 edition released in May 2013 replaces the DSM-IV-TR edition and the changes are as follows: symptoms can now occur by age 12 rather than by age 6, and for adults and adolescents age 17 or older, only 5 symptoms are needed instead of the 6 needed for younger children. 
Unchanged is the requirement that symptoms must be present for at least 6 months and they are inappropriate for developmental level; several symptoms were present before age 12 years; several symptoms are present in two or more settings (e.g., at home, school or work; with friends or relatives; in other activities); symptoms interfere with or reduce the quality of social, school, or work; and the symptoms are not better explained by another mental disorder (e.g., mood disorder, anxiety disorder, dissociative disorder, or a personality disorder. A patient may have both ADHD and ASD. Symptoms are now referred to as “presentations”: Combined, predominantly inattentive, and predominantly hyperactive-impulsive presentations.