Researchers suggest that increased academic standards since the 1970s have contributed to the rise in diagnosis of ADHD. "When we researched educational and public policy literature for studies that documented time children spent on academic activities, we were alarmed to find how substantially education had changed since the '70s," said Jeffrey P Brosco from University of Miami in the US.
"From time spent studying to enrolment rates in pre-primary programmes, everything had increased, and not surprisingly, in the past 40 years we also saw ADHD diagnoses double," said Brosco. Researchers found that from 1981 to 1997, time spent teaching 3- to 5-year-olds letters and numbers increased 30 per cent.
They also discovered that the percentage of young children enrolled in full-day programmes increased from 17 per cent in 1970 to 58 per cent in the mid-2000s. And 6- to 8-year-olds in 1997 saw time spent on homework increase to more than two hours a week, when a decade earlier their peers were studying less than an hour.
While ADHD is a neurobiological condition, researchers said it is influenced by age-dependent behaviours and demands of the environment.
As academic activities have increased, time for playing and leisure has decreased, resulting in some children being seen as outliers and ultimately being diagnosed with ADHD. "We feel that the academic demands being put on young children are negatively affecting a portion of them. For example, beginning kindergarten a year early doubles the chance that a child will need medications for behavioural issues," said Brosco.
Children should participate in learning activities that are developmentally age appropriate, researchers said. The findings were published in JAMA Pediatrics.