The academic hothousing of children as they spend too much time poring over books and screens inside is ruining their eyesight, prompting plans to force kids to spend more time outdoors while at school.
Eye experts say the excessive study habits of students at high academic achieving schools are driving an increase in the prevalence of myopia or short-sightedness in Australian children.
The Brien Holden Vision Institute at UNSW estimates that myopia levels have risen in the past 15 years from 20 per cent of Australian 17-year-olds to about 30 per cent.
"Kids who become myopic combine intensive study with not a lot of time outdoors," said ANU Professor Ian Morgan, who co-authored the landmark Sydney Myopia Study that established the link between exposure to sunshine and short-sightedness in Australian children.
In a bid to arrest the increase in myopia, UTS Orthoptics Professor Kathryn Rose is planning a two-year trial in 42 Sydney primary schools that act as feeders for high academic achieving secondary schools. Half of the 2000 students recruited would spend an extra hour a day at school outdoors, and another extra hour a day outside at home.
"At academically selective and high-achieving schools, there are substantially higher rates of short-sightedness than in ordinary schools," said Professor Rose, chief investigator of the Sydney Myopia study.
Myopia is particularly prevalent in Australian students from Asian migrant backgrounds, which culturally place a high value on education. Sixty per cent of 17-year-old students of east Asian background are short-sighted, compared with 18 per cent of children of European ancestry, a follow-up study found.
"We do have a problem group of children in Australia, they're from Chinese and east Asian origin who bring their intensive study habits with them," Professor Morgan said. "The big target area is ethnic communities in which education has culturally been seen as the top priority of childhood."
Professor Rose said the problem was now spilling over into children of European background, as some learn from the study habits of migrant children to compete.
"The rate of myopia is going up in European students," Professor Rose said. "When people become quite competitive around education they adopt some of the [study] behaviours."
Between 2005 and 2011, the proportion of Caucasian 12-year-olds with myopia increased from 4 per cent to 9 per cent, while the proportion of 12-year-olds of Asian ethnicity with myopia rose from 39 per cent to 53 per cent. Different demographic composition means that Sydney has a higher prevalence of myopia than Perth.
However, Australia's myopia problem pales in comparison to countries like Taiwan, South Korea, Hong Kong, Singapore and China, where 80 to 90 per cent of students are short-sighted.
While experts agree that screen devices could be exacerbating eyesight problems by giving kids another reason to stay indoors, they say it is the lack of outdoor time rather than the screens themselves that is ruining children's eyes.
Overseas studies have shown spending an extra 10 to 14 hours a week can reduce the number of new cases of myopia by 25 to 50 per cent. "If you could get within the school system [students spending] two to three hours a day outside, you could bring the situation substantially under control," Professor Morgan said.