Corrections outperform expertise-based interventions for countering misinformation from alternative medicine sources

Given that health-based misinformation can cause serious harm, designing effective interventions is paramount. Recently, misinformation interventions that target a source's relevant expertise have shown promise, with findings suggesting they may provide a comparative advantage to corrections for countering misinformation spread by disinformation health sources. However, whether such a benefit extends to other sources of health misinformation, such as alternative medicine practitioners, remains to be empirically assessed. Across two preregistered experiments (N = 1,410) participants were exposed to cancer misinformation attributed to an alternative medicine source (e.g., a homeopath), before receiving either a no-intervention control, a correction intervention, a generic low expertise intervention (Experiment 1), or a targeted low expertise intervention, which either did or did not reveal that the source was deceitful (Experiment 2). All interventions reduced belief in misinformation and perceptions of source credibility relative to the control condition. However, across both studies presenting corrections was equivalent to, or more effective than, all low expertise conditions, even when the expertise-based intervention revealed that the source had deceptively misrepresented their credentials. This suggests that correcting false claims is more effective than highlighting an alternative medicine practitioner's lack of expertise, emphasizing the need to tailor interventions to the misinformation source.