Older Americans are disproportionately more likely to share fake news on Facebook, according to a new analysis by researchers at New York and Princeton Universities. Older users shared more fake news than younger ones regardless of education, sex, race, income, or how many links they shared. In fact, age predicted their behavior better than any other characteristic — including party affiliation.

The role of fake news in influencing voter behavior has been debated continuously since Donald Trump's surprising victory over Hillary Clinton in 2016. At least one study has found that pro-Trump fake news likely persuaded some people to vote for him over Clinton, influencing the election's outcome. Another study found that relatively few people clicked on fake news links — but that their headlines likely traveled much further via the News Feed, making it difficult to quantify their true reach. The finding that older people are more likely to share fake news could help social media users and platforms design more effective interventions to stop them from being misled.

Today's study, published in Science Advances, examined user behavior in the months before and after the 2016 US presidential election. In early 2016, the academics started working with research firm YouGov to assemble a panel of 3,500 people, which included both Facebook users and non-users. On November 16th, just after the election, they asked Facebook users on the panel to install an application that allowed them to share data including public profile fields, religious and political views, posts to their own timelines, and the pages that they followed. Users could opt in or out of sharing individual categories of data, and researchers did not have access to the News Feeds or data about their friends.