Though several sources agree that attention deficit/hyperactivity disorder (ADHD) is is on the rise, new numbers question how much. According to a recent study published in JAMA Pediatrics , diagnoses of ADHD increased 24 percent in Southern California over the past 10 years, bringing to issue previous estimates. As part of the study, doctors reviewed the charts of children treated at the Kaiser Permanante Southern California physician’s group from 2001 to 2010 – 842,830 children in all. They found that in 2001, 2.5 percent of children age 5 to 11 were diagnosed with ADHD, but that number increased to 3.1 percent in 2010. The Centers for Disease Control and Prevention (CDC) estimates that about 9.5 percent of children age 4 to 17 have ADHD. Researchers in the California study believe their estimate gives a more accurate picture of the rate of ADHD in Southern California because they reviewed actual medical records, rather than relying on parents to respond to telephone surveys, which is how the CDC got its number. Furthermore, the majority of ADHD diagnoses in the California study were made by specialists using strict Diagnostic and Statistic Manual of Mental Disorders ( DSM-IV ) diagnoses. This complicates previous estimates, as new research found that only 38 percent of primary care physicians actually use the DSM-IV for diagnosing ADHD.