Captions on children's programmes could help them learn to read

The way children learn to read is a developing science - and one study has discovered subtitles or captions may help.

In the UK, that's prompted a campaign calling for subtitles to be put on all children's programmes.

But here in New Zealand, an expert says if it sounds too good to be true, it is.

By turning on the subtitles, the more they watch the more they're reading without even realising it.

UK campaign 'Turn On The Subtitles' is calling for same-language subtitles to be on by default for all kids' programmes.

Celebrities are backing it.

"What takes ten seconds, costs nothing but could help change your child's life forever?" Stephen Fry asks.

UK Prime Minister Boris Johnson is also voicing his support.

"Massive support for subtitles," he says on Twitter.

The campaign draws on an academic study of 2350 children, of which 34 percent became good readers with just schooling.

But that number doubled to 70 percent when they were exposed to 30 minutes of subtitled film songs per week.

It's hard to ignore the words when they're on screen, and it's this incidental reading mileage that could help children's learning.

But here in New Zealand international literacy development expert Professor Brigid McNeill isn't convinced.

"It's probably a little bit too good to be true," she says.

She says subtitles won't do any harm and may be useful for children learning a second language - but they're no silver bullet.

"There's not a lot of evidence for it being more effective than other things we know are helpful for children learning to read," Prof McNeill says.

And that's parents reading to their children.

"In a way that they hear sounds and words, be able to blend sounds together being aware of letters and sounds and having quality conversations," Professor McNeill says.

So there's no getting out of those bedtime stories just yet.