Intellectual overconfidence and susceptibility to anti-science misinformation

Anti-science misinformation can undermine trust in science, and understanding who is most susceptible is important for combatting its influence. One relevant trait is Intellectual Humility (IH), associated with greater understanding of science and the reasoning skills required to reject misinformation. Three pre-registered experimental studies (total N = 1604) examined IH and susceptibility to anti-science misinformation in the context of consumer genetic testing. A central subscale of IH – Lack of Intellectual Overconfidence – emerged as the strongest predictor, with intellectually overconfident individuals most susceptible to misinformation, though effect sizes were modest. The final study introduced a warning-label intervention that had a small positive effect on reduced susceptibility to misinformation about genetic testing companies, but only for participants with less intellectual overconfidence, suggesting that those who would benefit most from such interventions may be least likely to do so.