According to new research published in Scientific progress. The findings are consistent with the Dunning-Kruger effect, a well-documented phenomenon in which people who lack skills or knowledge tend to overestimate their abilities.
“I’m interested in public understanding of science because it’s extremely important to the well-being of society and the environment,” said study author Nick Light, an assistant professor of marketing at Portland State University. “When people act in ways that go against good science, people get sick, lose their homes, lose money, get displaced, or even die (as is the case with COVID, natural disasters, etc.). The better we can understand why people hold attitudes that run counter to the scientific consensus, the better scientists or policymakers can design interventions to help people.
In two initial studies involving 3,249 American adults recruited by Amazon Mechanical Turk and Prolific Academic, participants were randomly assigned to indicate their level of support or opposition to one of seven scientific issues: climate change, genetically modified foods, nuclear energy , vaccination , evolution, the Big Bang or homeopathic medicine. Participants were asked to rate their understanding of the topic on a 7-point scale ranging from “Unclear understanding” to “Full understanding”.
To assess their scientific knowledge, participants then answered 34 randomly ordered true-false questions. The questions covered a wide range of scientific topics, including True or False? The center of the earth is very hot”, “True or false? All insects have eight legs’ and ‘True or False? Venus is the closest planet to the sun.
Light and his research team found that people who were more opposed to the scientific consensus on a topic were more likely to claim to have a “deep understanding” of it. But those who were more opposed to the scientific consensus tended to score worse on the test of objective scientific knowledge.
“Scientists are constantly debating the best ways to explain the world around us,” Light told PsyPost. “However, sometimes the evidence is so strong or consistent that most of them agree on something. This is what we call scientific consensus. In this paper, we find that people who hold attitudes more strongly against the scientific consensus think they know the most about scientific issues, but actually know the least.
The researchers also found some evidence that political polarization may weaken these relationships. For more politically polarized issues, the relationship between opposition to scientific consensus and objective knowledge was not as negative.
“The main caveat is that although this pattern of effects seems quite general, we don’t find it for all problems,” Light said. “One notable example is climate change. Our next steps involve really digging deeper into psychology to try to understand why we don’t find these effects for some problems.
In a third study involving 1,173 US adults, participants were given the opportunity to bet on their ability to score above average on a test of objective science knowledge. Consistent with previous studies, Light and his colleagues found that participants with greater opposition to the scientific consensus tended to earn less due to overconfidence in knowledge.
In a fourth study, which included 501 participants, the researchers examined whether overconfidence in knowledge was associated with willingness to receive a COVID-19 vaccine. The study was conducted in July 2020, before the vaccine was publicly available. Participants were asked if they would be willing to receive a vaccination in the future and then rated their understanding of how a vaccine against COVID-19 would work.
Participants then completed a 23-question science knowledge test that included six items about COVID-19, such as “True or false? COVID-19 is a type of bacteria’ and ‘True or False? COVID-19 can be transmitted by houseflies.”
Light and colleagues found that participants who were more opposed to receiving a vaccine tended to report having a better understanding of how the COVID-19 vaccine would work, but their general knowledge of science and COVID- 19 are usually worse.
A fifth survey of 695 participants conducted in September 2020 found a similar pattern of results regarding policies to mitigate COVID-19. The results held even after controlling for political identity.
The researchers said the findings have some practical implications for science communicators and policymakers.
“Given that the most extreme opponents of the scientific consensus tend to be those most confident in their knowledge, evidence-based educational interventions are less likely to be effective for this audience,” Light and colleagues write . “For example, the Ad Council ran one of the largest public education campaigns in history in an effort to convince people to get a COVID-19 vaccine. If people who have strong anti-vaccine beliefs already think they know everything they need to know about vaccination and COVID-19, then the campaign is unlikely to convince them.”
The study, “Knowledge Overconfidence Is Associated with Anti-Consensus Views on Controversial Scientific Issues,” was authored by Nicholas Light, Philip M. Fernbach, Nathaniel Rabb, Mugur V. Geana, and Stephen A. Sloman.