Is too much screen time for Hong Kong children causing short-sightedness? The Post takes a closer look at the city’s growing myopia rate

Researchers studied the prevalence of the condition across three periods in 2015 to 2021.

The rate stood at 23.8 per cent from 2015 to 2019 and gradually rose to 28.8 per cent between the start of pandemic in 2020 and February 2021 when stringent restrictions were in place, such as the closure of school campuses.

The data showed cases increased significantly among 6-year-olds during the pandemic, almost doubling to 25.2 per cent in 2021 from the pre-Covid level of 13.9 per cent.

What are the contributing factors?

Dr Jason Yam Cheuk-sing, the study’s lead author and an associate professor at the university’s department of ophthalmology and visual sciences, said factors such as less time outdoors, changes in reading habits and more screen usage had contributed to myopia rates.

“Our lifestyles have changed. Even after the end of the pandemic, our lifestyles did not return to those of pre-Covid times,” he said.

The researchers behind the study also warned that the prevalence of myopia could remain high in the coming years.

Covid-19 rules contributed to upsurge in myopia in Hong Kong children, study finds

Why have pandemic habits continued?

Langton Cheung Yung-pong, honorary chairman of the Aided Primary School Heads Association, said the pandemic had accelerated the development of digital learning, a practice that was already encouraged by schools and authorities beforehand.

“After the pandemic, schools will not backtrack after the digital learning platforms have been established,” he said. “There are no longer online classes … but classes still feature lots of digital learning platforms that require the use of computers.”

Cheung noted some schools required students to read an online article written in Chinese everyday to build up their comprehension skills.

But the association honorary chairman said the increase in screen time was not entirely due to studies, since schools typically limited the number of hours for digital learning, and many children used electronic devices in situations such as travelling or eating out.

Cheung also pointed to the habit of devices being used as “electronic pacifiers” to keep children quiet, potentially contributing to myopia rates.

Pandemic contributing to ‘myopia boom’ among Hong Kong children, study finds

Are similar trends being reported elsewhere?

An increase in the prevalence of myopia among children during the pandemic was also reported in other locations.

In 2021, a study by mainland Chinese researchers found the rate of nearsightedness accelerated amid a period of pandemic lockdowns and later partially receded after such restrictions were eased.

Scholars in South Korea also published a paper in the same year that noted a substantial increase in the progression of the condition during the pandemic.

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What can parents and children do?

Associate professor Yam encouraged parents to increase the time children spent outdoors to two hours a day and promote good reading habits.

He said good habits included not reading for more than 30 minutes a session, keeping one’s eyes at least 30cm (11.8 inches) from the book or device and avoiding doing so in a dark environment.

Readers should also keep ceiling and desk lights on during the session, he added.

Additional reporting by Harvey Kong