Do Fact Checks Help Combat COVID-19 Misinformation?

Ute Eppinger

February 17, 2022

Social networks such as Facebook and Twitter are full of misinformation about COVID-19, and public-health officials and the media are spending a lot of time and energy to counter it. But is it worth it?

Fact checks can indeed correct misconceptions, according to results from a study published in Nature Human Behaviour, but the effect is not long lasting.

In that study, participants from Canada, Great Britain, and the United States were pregistered for surveys conducted by political scientist Brendan Nyhan, PhD, from Dartmouth College in Hanover, New Hampshire, and his colleagues. They were then randomly exposed to articles in which COVID-19 misinformation had or had not been fact-checked. All participants were subsequently interviewed and asked to evaluate true and false claims about COVID-19.

Those who read the fact-checked articles were able to debunk the fake claims more frequently; however, this effect disappeared almost completely in just a few weeks.

In addition, the opinion of the participants only changed for specific topics covered in the fact-checked articles. Nyhan and his colleagues found no evidence that the effect was transferred to other misconceptions about COVID-19. Repetition of the fact checks after a few weeks did nothing to increase their effect.

"Not a Miracle Weapon"

"Fact-checked texts can significantly reduce a reader’s belief in misinformation," said Sabrina Heike Kessler, PhD, from the Institute for Communications Science and Media Research at the University of Zurich, who noted that this was demonstrated in a 2018 meta-analysis.

The study by Nyhan's team "confirms that fact checks are not completely ineffective, but they are also not a miracle weapon in the fight against misinformation," said Christian Hoffmann, PhD, from the Institute for Media and Communications Science at the University of Leipzig in Germany.

The study also shows that fact checks can lead to an adjustment in an individual's assessment, added Lena Frischlich, PhD, communications scientist and media psychologist at the University of Münster in Germany.

"However, this adjustment is not particularly stable," she said. "If the correct answer is not recalled, then the evaluation of the misinformation returns to its previous level. If you think back to your schooldays for a metaphor, the question is raised as to whether any actual learning took place through the fact check, or if the correct answer is simply being recited."

"The largest effects are seen under relatively artificial lab conditions," where this study was conducted, Hoffmann pointed out. "The closer the examined scenario is to real life, the milder the detectable effects," he said, citing one recent study. It must therefore be assumed that the effects of the fact checks are much smaller in everyday life than they are in the study. In fact, the effects of fact checks on the overall attitudes or behavior of the participants were barely noticeable.

The research also demonstrated that, in the long-term, the effect of misinformation is not completely eliminated with a correction, a phenomenon known as "continued influence effect." Unfortunately, this effect also grows stronger with time.

"The old proverb is true: mud sticks. And accordingly, misconceptions often continue to influence the thinking and actions of people, despite a correction," said Kessler.

It has been known since the 1990s how difficult it is to overwrite the continued influence effect, said Nicole Krämer, PhD, head of the Department of Social Psychology at the University of Duisburg-Essen in Germany.

"Even if people believe the new corrected information, the original information remains more present with later queries, since it was plausibly incorporated into the knowledge structure." The corrective information is only successful if it is so closely tied to existing knowledge structures — "for example, through higher plausibility — that the old (false) information is overwritten in the long-term," she explained.

"Vaccination Against Misinformation" Works Best

It is important to curb the spread of hoaxes from the outset. "If misconceptions are held as the truth by someone just once, they are anchored in that person’s mind relatively securely and cannot be eliminated completely," said Kessler. "You then need specific rebuttal strategies that will also be carefully read, processed, and stored by those people."

"But fundamentally, any attempt at rebuttal is better than no attempt at all," she said.

However, research shows that preventive "vaccination against misinformation" is still more effective than fighting the misconception after the fact, Kessler added. This means making people aware of the risks of disseminated misinformation and simultaneously carrying out a preventive rebuttal. "This then generally improves their ability to recognize misinformation," she explained.

The correction of misconceptions creates a mental gap. "In psychology, this is called a gap in the mental model. Gaps that have formed must be closed so that misinformation can no longer have a footing there. A rebuttal can be fact-based, logic-based, or source-based here," said Kessler.

It should also be explained why such fake news existed and was spread in the first place. "Ideally, the explanation is more scientifically assured and more plausible than the fake news, and is communicated briefly and in a simple-to-understand manner," said Kessler. She believes that consistent rebuttal is important, especially in the context of COVID-19. "The reason we have not achieved herd immunity in Germany, despite vaccinations being available, is in part the result of people’s widespread misconceptions."

Spread Reliable Information More Widely

The assumption that internet users happen upon misinformation and are then strongly influenced by it has not been substantiated. The spread of misinformation is not that great overall, said Hoffman.

"Misinformation is predominantly sought and spread by people who strengthen their view of the world by doing so, and want to convince or criticize others," he explained. "However, it is precisely these small, determined groups that are particularly resistant to fact checks." It is more important, therefore, to ensure "that reliable information continues to have a much larger distribution" than it is to correct individual instances of misinformation through fact checks.

People stop spreading misinformation if they are prompted to consider the reliability of the information they are looking at, one analysis indicates. Evidence also suggests that the effectiveness of fact checks can be increased if the values of the person being corrected are reflected. "In practice, this happens far too rarely," said Hoffmann.

Still, the effect of fact checks should be examined in more detail. "Is a detailed analysis of the facts actually taking place — a learning experience — or are fact checks more often used as a shortcut to assess information?" Frischlich asked. "We also must better understand how to can counteract this decline in fact checks."

The importance of accurate information on the internet should not be underestimated, said Frischlich. "Even if the study does not focus on these aspects, it depends on how the fact checks are structured. The Debunking Handbook offers practical tips on how this can be achieved."

Nat Hum Behav. Published online February 3, 2022. Full text

This article originally appeared in the German edition of Medscape.

Follow Medscape on Facebook, Twitter, Instagram, and YouTube


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.