The Debunking Handbook is a guide to debunking myths, by John Cook and Stephan Lewandowsky. It boils down the research on the psychological research on misinformation into a short, simple summary.
This is part two of a five-part series cross-posted from Skeptical Science.
To debunk a myth, you often have to mention it — otherwise, how will people know what you’re talking about? However, this makes people more familiar with the myth and hence more likely to accept it as true. Does this mean debunking a myth might actually reinforce it in people’s minds?
To test for this backfire effect, people were shown a flyer that debunked common myths about flu vaccines.1 Afterwards, they were asked to separate the myths from the facts. When asked immediately after reading the flyer, people successfully identified the myths. However, when queried 30 minutes after reading the flyer, some people actually scored worse after reading the flyer. The debunking reinforced the myths.
Hence the backfire effect is real. The driving force is the fact that familiarity increases the chances of accepting information as true. Immediately after reading the flyer, people remembered the details that debunked the myth and successfully identified the myths. As time passed, however, the memory of the details faded and all people remembered was the myth without the “tag” that identified it as false. This effect is particularly strong in older adults because their memories are more vulnerable to forgetting of details.
How does one avoid causing the Familiarity Backfire Effect? Ideally, avoid mentioning the myth altogether while correcting it. When seeking to counter misinformation, the best approach is to focus on the facts you wish to communicate.
Not mentioning the myth is sometimes not a practical option. In this case, the emphasis of the debunking should be on the facts. The often-seen technique of headlining your debunking with the myth in big, bold letters is the last thing you want to do. Instead, communicate your core fact in the headline. Your debunking should begin with emphasis on the facts, not the myth. Your goal is to increase people’s familiarity with the facts.
- Skurnik, I., Yoon, C., Park, D., & Schwarz, N. (2005). How warnings about false claims become recommendations. Journal of Consumer Research, 31, 713-724.