Discrediting health disinformation sources: Advantages of highlighting low expertise.

Disinformation is false information spread intentionally, and it is particularly harmful for public health. We conducted three preregistered experiments (N = 1,568) investigating how to discredit dubious health sources and disinformation attributed to them. Experiments 1 and 2 used cancer information and recruited representative U.S. samples. Participants read a vignette about a seemingly reputable source and rated their credibility. Participants were randomly assigned to a control condition or interventions that (a) corrected the source's disinformation, (b) highlighted the source's low expertise, or (c) corrected disinformation and highlighted low expertise (Experiment 2). Next, participants rated their belief in the source's disinformation claims and rerated their credibility. We found that highlighting low expertise was equivalent to (or more effective than) other interventions for reducing belief in disinformation. Highlighting low expertise was also more effective than correcting disinformation for reducing source credibility, although combining it with correcting disinformation outperformed low expertise alone (Experiment 2). Experiment 3 extended this paradigm to vaccine information in vaccinated and unvaccinated subgroups. A conflict-of-interest intervention and 1 week retention interval were also added. Highlighting low expertise was the most effective intervention in both vaccinated and unvaccinated participants for reducing belief in disinformation and source credibility. It was also the only condition where belief change was sustained over 1 week, but only in the vaccinated subgroup. In sum, highlighting a source's lack of expertise is a promising option for fact-checkers and health practitioners to reduce belief in disinformation and perceived credibility. (PsycInfo Database Record (c) 2024 APA, all rights reserved).