Studies have suggested that excessive exposure to screen-based media may have negative health implications for children and adolescents.
In 2001, the American Academy of Pediatrics (AAP) set guidelines recommending that children under the age of 2 years should have no exposure to screen-based media, while children and adolescents over the age of 2 years should not be exposed to such media for more than 2 hours a day.
But lead researcher Stephen Houghton, of the Graduate School of Education at The University of Western Australia in Perth, Australia, and his team found that screen-based media use is now central to the everyday lives of young people, suggesting such guidelines may be unrealistic.
The team publishes their findings in the journal BMC Public Health.
Past studies have suggested that excessive exposure to screen-based media may have negative health implications for children and adolescents.
In 2013, Medical News Today reported on a study claiming too much time spent watching TV, playing video games and surfing the Internet may harm children's well-being and increase anxiety.
Another study published in May 2014 found children who spend more than 2 hours a day using screen-based media are at higher risk of hypertension, while a more recent study earlier this month found the presence of small-screen devices in a child's bedroom could disrupt sleep.
Similar evidence led the AAP to make recommendations to limit the use of screen-based media in children and teenagers. "Children and teens should engage with entertainment media for no more than 1 or 2 hours per day," the organization states, "and that should be high-quality content. It is important for kids to spend time on outdoor play, reading, hobbies and using their imaginations in free play."
Houghton and his team note, however, that these guidelines only focus on use of screen-based media for entertainment purposes as opposed to educational purposes.
"The growing concern for the long-term impact of screen-based media use on health across the lifespan suggests there is a need to focus on all screen-based media use," say the researchers.
"Furthermore, the increasing use of screen-based media use in regular primary (elementary) school and high school classrooms during the regular school day, and for homework purposes, and for social networking need also to be taken into account if a more accurate estimate of screen-based media use and its consequences (positive and negative) are to be ascertained."
63% of children spend more than 2 hours a day using screen-based media
For their study, Houghton and his team conducted an online survey with 2,620 children aged 8-16 years from 25 elementary and high schools across Australia.
The children were shown pictures of different screen-based technology - including a TV, laptop computer, iPad, iPhone, iPod Touch, Portable Playstation (PSP) and Xbox - and asked to select which devices they use.
They were then shown a variety of activities they could use each device for - such as watching TV, surfing the Internet, doing school work and homework and using social networking sites - and asked to select which activities apply to them.
Finally, they were asked how many hours they use these devices for on an average day, from when they wake up until they go to bed.
Overall, the team found that 63% of all children surveyed reported using screen-based media for longer than the maximum 2 hours a day recommended by the AAP. From assessing individual age groups, the researchers found 45% of 8-year-olds and 80% of 14-15-year-olds reported spending more than 2 hours a day using screen-based media.
When it came to playing video games, it was unsurprising that boys were more likely to exceed the AAP recommendation than girls. What did surprise the team, however, was that girls were more likely than boys to exceed the AAP recommendation by using screen-based media for social networking, watching TV and movies and surfing the Internet.
"Of particular interest is the rate at which girls are more likely to exceed the less than 2 hours recommendation for social networking as they got older," notes Houghton. "Specifically, by 15 years of age girls were over 15 times more likely to exceed the less than 2 hours recommendation compared with their 8-year-old peers, and almost seven times more so than boys."
Evidence-based recommendations on screen-based media use required
The team notes that their study did not investigate how the children's use of various screen-based technology affected their health, but say this is something that needs to be addressed in future research.
However, what their findings suggest, the researchers say, is that the current guidelines for screen-based media use may not be plausible:
"Screen-based media use plays a pertinent and relevant role in the everyday lives of young people, and both parents and schools are enthusiastically embracing the digital age.
Consequently, the less than 2 hours per day recommendation may no longer be tenable given the surge in social media engagement and school-derived screen-based media use."
"Further research is now required to develop evidence-based screen-based media use guidelines for children and adolescents in relation to the mental, social and physical health impact of such behaviors," they add.
"Furthermore, as researchers, educators and health-related professionals seek to develop such guidelines for appropriate screen-based media use, they would do well to take cognizance of the extent to which screen use differs across form, activity, sex and age."