My Topics

19 February 2020

Do people believe what they want to believe? Scientific facts matter!

Some people hold beliefs that are false. This can be harmful when these false beliefs concern health issues, such as vaccination and food safety. A study in Science Communication investigated the extent to which people are receptive to scientific facts about vaccines and food additives. The results show that people use scientific facts to correct their false beliefs, but the extent to which they do so depends on their personal goals.

Take aways

  • People who hold a false belief about vaccines and food additives are quite receptive to clear, scientific information. By simply communicating the facts they can be persuaded to update their belief.
  • However, people who are motivated to hold on to the false belief change their mind less easily when confronted with scientific facts than people who are motivated to come to an accurate conclusion.
  • Science communicators should be aware of an individual’s goal in processing science-based information. They are advised to motivate people to view information in a balanced way and from different perspectives and refrain from putting people in a defensive mindset.

Study information

  • Who?

    1,256 participants (mean age: 37; age range 18-74; ~67% female).

  • Where?

    United Kingdom

  • How?

    Two studies were conducted. Both studies included participants who held a false belief with regard to a certain topic (Study 1: vaccines can ‘overload’ a child’s immune system, Study 2: food additives indicated with E numbers are unsafe to consume). They were instructed to read correct scientific facts about the above-mentioned topics, either with the goal to protect their belief, or with the goal to come to the most accurate conclusion, or like they normally would. After reading the scientific facts, the beliefs of the participants were measured again. Beliefs were measured on a scale ranging from I am 100% certain this is false (-100) to I am 100% certain this is true (100), with I don’t know in the middle (0).

Facts and findings

  • A large part of the participants changed their belief after reading the scientific facts:
    • In Study 1, participants reduced thei strength of their belief in the vaccine-misperception from about 60% sure that it was true to about 20% sure that it was true. So, they still thought their false belief was correct, but became less sure about it.
    • In Study 2, participants changed their belief in the food safety-misperception from about 55% sure that it was true to about 10% sure that it was false. In other words, the perception of their false belief changed from true to false.
  • Participants who were instructed to read the scientific facts with the goal to come to the most accurate conclusion were about 1.3 times more likely to change their belief (from true to false) than participants who were instructed to read the same facts with the goal to protect their belief.
  • Participants who did not receive any instructions on how to read the facts were just as likely to change their belief as the participants who were instructed to read the facts with the goal to come to the most accurate conclusion.
  • Study 2 shows that people’s beliefs about food additives go hand-in-hand with their attitude towards food-related policies and their own eating behavior: participants who were less convinced of the fact that food additives indicated with E numbers are unsafe to consume also showed less support for policies aiming to reduce the use of E numbers and intended to avoid eating food products with E numbers less.