Responsive view Posting ; In a 2016 Centers for Disease Control and Prevention study, scientists found that 6.1 million children aged 2-17 years living in the U.S. had been diagnosed with attention-deficit/hyperactivity disorder (ADHD), which is similar to previous en Ages 6-11: Approximately 2.4 million children Ages 12-17: Approximately 3.3 million children Aa list for diagnosing ADHD list Three types of ADHD and the accompanying characteristics. Predominantly inattentive type. The student may: o submit inaccurate or incomplete work, o have difficulty attending to conversations, activities, or tasks,