YouTube plans to show adverts that educate people about disinformation techniques, following a successful experiment by Cambridge University.
Researchers found the videos improved people’s ability to recognise manipulative content.
They will be shown in Slovakia, the Czech Republic and Poland to combat fake news about Ukrainian refugees.
Google said the “exciting” findings showed how social media can actively pre-empt the spread of disinformation.
The research was founded on a developing area of study called “prebunking”, which investigates how disinformation can be debunked by showing people how it works – before they are exposed to it.
In the experiment, the ads were shown to 5.4 million people, 22,000 of whom were surveyed afterwards.
After watching the explanatory videos, researchers found: an improvement in respondents’ ability to spot disinformation techniques an increased ability to discern trustworthy from untrustworthy content an improved ability to decide whether or not to share content.
The peer-reviewed research was conducted in conjunction with Google, which owns YouTube, and will be published in the journal Science Advances.
Beth Goldberg, head of research and development for Google’s Jigsaw unit which focuses on tackling online security dangers, called the findings “exciting”.
“They demonstrate that we can scale prebunking far and wide, using ads as a vehicle,” she said.
Jon Roozenbeek, the lead author on the paper, told the BBC the research is about “reducing the probability someone is persuaded by misinformation”.
“Obviously you can’t predict every single example of misinformation that’s going to go viral,” he said. “But what you can do is find common patterns and tropes.
“The idea behind this study was – if we find a couple of these tropes, is it possible to make people more resilient against them, even in content they’ve never seen before?”
The scientists initially tested the videos with members of the public under controlled-conditions in a lab, before showing them to millions of users on YouTube, as part of a broader field study.
The anti-misinformation campaign and prebunking campaign was run on YouTube “as it would look in the real world”, Roozenbeek said.
“We ran them as YouTube ads – just like an ad about shaving cream or whatever… before your video plays,” he explained.