Children who turn 5 right before kindergarten are more likely to be diagnosed with attention deficit / hyperactivity deficiency than their oldest classmates. The finding reinforces the concern that a general nervous system disorder may be re-diagnosed.
“We think … this is the relative age and relative immaturity of children born in August in any class, which increases the likelihood that they have been diagnosed with ADHD,” says Anupam Jena, doctor and economist at Harvard Medical School,
Jena and his colleagues analyzed data on insurance claims for more than 407,000 children born from 2007 to 2009. In states that require children under 5 to start day care, children born in August were 34% more likely to be diagnosed with ADHD than were born almost a year ago in September – immediately after the cut-off date. For children in August, 85.1 per 10,000 children were diagnosed with ADHD, compared with 63.6 per 10,000 for September children, researchers report on November 29. New England Journal of Medicine,
People with ADHD usually have symptoms of inattention, hyperactivity, and impulsivity that are severe or frequent enough to interfere with their daily lives. In 2011, 11 percent of children aged 4 to 17 years were reported to have a diagnosis of ADHD, which is higher than in most other countries. Differences between states also suggest overdiagnosis, says Jena, “if there is something different in different states.” For example, while in Kentucky, about 19% of children between the ages of 4 and 17 were reported to have been found, the rate was about 12 percent in neighboring West Virginia.
“Greater adherence to ADHD is good,” because this condition can lead to reduced academic success, poor social skills and substance abuse, says Stephen Hinshaw, a clinical and developmental psychologist at the University of California at Berkeley who is not participating in the study, but a brief visit can leads to inaccurate diagnosis, he says, if other factors or conditions are not excluded.
"Children mature at different rates," says Hinshaw. Many problems in childhood, from anxiety to communicating with overcrowded classes, can resemble ADHD.
“We don’t want to over-react to inattention, lack of attention, impulsive behavior and a large amount of excessive activity,” he says. "We need to understand the other skills of the child."