The University of Hong Kong (HKU)’s Department of Paediatrics and Adolescent Medicine has announced the findings of a cohort study and a large cross-sectional study on the use of digital devices among Hong Kong children in the past five years (2012–2017).

Alarming results revealed that the time spent on digital devices by Hong Kong children was much higher than other areas in the world. Based on the findings, the researchers concluded excessive use of digital devices without parental guidance has negative impacts on children’s behaviour, academic performance, and physical health status.

Usage of digital devices is positively associated with ADHD

A total of 7,585 primary one to primary three students from 51 schools were recruited for the population-based study in 2016. Their daily time spent on digital device use was recorded to access the risk of Attention-Deficit Hyperactivity Disorder (ADHD).


From the survey, it was found that 74.8% of children spent more than two hours on digital device use. In comparison, the figure was 20.8% in United States and 47.4% in Beijing, China. On average, children spent more than three hours on school days and seven hours in holidays on digital devices which is equivalent to half of their leisure time.

More disturbingly, the researchers observed a positive link between screen time and risk of ADHD. Such duration effect was insignificant when parents provided guidance on children’s television viewing and video gaming.


Excessive use of digital devices poses negative impacts on children’s physical and mental health

In another study, a cohort of 681 children were followed from kindergarten (at age five; academic year 2011-12) to primary school (at age nine; academic year 2014-15) with detailed records on the use of digital devices and assessments on behavioural, psychosocial, and academic outcomes.

Results showed that pre-schoolers who spent more time on television viewing and video gaming at age five were more likely to be overweight, have behavioural problems including emotional problems and hyperactivity as well as poor academic performance at age nine.


Hong Kong children less fit than counterparts in the West and other parts of Asia

The research team also looked into children’s physical fitness by analysing data of the School Physical Fitness Award Scheme in 2016/17. Alarmingly, the flexibility, muscle strength, and cardiorespiratory fitness of Hong Kong students were lower than peers in China, Singapore, and Europe.

Back in 2006, HKU has also found that only 6.1% of our children participated in 60 minutes of physical activity every day, which is recommended by the World Health Organisation (WHO). Although the figure has risen to 8.3% in an official report in 2011, children’s physical fitness remains a serious public health concern in Hong Kong.

Yet, excitingly, longitudinal data showed that the School Physical Fitness Scheme can help physically less fit students to improve these attributes over three years. Hence, the research team recommends schools to actively participate in the School Physical Fitness Award Scheme and develop sports mentorship programmes. MIMS

Read more:
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