Tips on how to limit excessive screen time

Andy, whose son is 14, contacted the BBC to say he was disappointed by the advice.

"There is absolutely no doubt in my mind that screen time is damaging school performance and sports performance and dangerously addictive.

"I have had to restrict my son's screen time to a Friday after school and a Saturday, due to lack of focus at school. His default was to head straight to the Xbox (which I would certainly classify as screen time... it is just a game after all which most boys are engaging in across all devices).

"After some grumbling, he has settled in and we have seen an improvement in school performance.

"I coach the under-15 football team and it is very clear, even with a 14:00 kick-off on a Sunday, who has been up all night on some form of screen."

Anne Longfield, the children's commissioner, believes guidance is sorely needed by parents.

"The fact that there isn't enough evidence doesn't mean we shouldn't have a view and try to work out what's best to do. Children are getting screens earlier, the average age to get a smartphone is now nine. Parents tell me that it is the one thing that drives them mad, causes huge rows, and they don't know what to do about it.

"Parents are worried their kids will be socially damaged if they don't give them a phone, so they're in a tough spot."

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