ABSTRACT
Background
Vaccination coverage needs to reach more than 80% to resolve the COVID-19 pandemic, but vaccine hesitancy, fuelled by misinformation, may jeopardize this goal. Unvaccinated older adults are not only at risk of COVID-19 complications but may also be misled by false information. Prebunking, based on inoculation theory, involves ‘forewarning people [of] and refuting information that challenges their existing belief or behavior’.
Objective
To assess the effectiveness of inoculation communication strategies in countering disinformation about COVID-19 vaccines among Canadians aged 50 years and older, as measured by their COVID-19 vaccine intentions.
Method
Applying an online experiment with a mixed pre–post design and a sample size of 2500 participants, we conducted a national randomized survey among English and French-speaking Canadians aged 50 years and older in March 2021. Responses to two different disinformation messages were evaluated. Our primary outcome was the intention to receive a COVID-19 vaccine, with attitudes toward COVID-19 vaccine a secondary outcome. The McNemar test and multivariate logistic regression analysis on paired data were conducted when the outcome was dichotomized. Wilcoxon sign rank test and Kruskal–Wallis were used to test difference scores between pre- and post-tests by condition.
Results
Group comparisons between those who received only disinformation and those who received the inoculation message show that prebunking messages may safeguard intention to get vaccinated and have a protective effect against disinformation.
Conclusion
Prebunking messages should be considered as one strategy for public health communication to combat misinformation.
Acknowledgement
We are grateful to Bobbi Rotolo for the manuscript technical and language editing.
Disclosure statement
No potential conflict of interest was reported by the author(s), but Cornelia Betsch, Philipp Schmid, Sander L van der Linden, Stephan Lewandowsky received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 964728 (JITSUVAX)” and Holly Witteman is funded by a Canada Research Chair in Human-Centred Digital Health.
Ethical approval
This study was approved by the Laval University Research Ethics Board (Comité d’éthique en recherche de l’Université Laval, CERUL). 2021-011/02-02-2021.
Additional information
Funding
Notes on contributors
Maryline Vivion
Maryline Vivion, Eve Dubé, Michelle Driedger, Devon Greyson, Janice Graham, Noni MacDonald, Samantha B. Meyer, Audrey Steenbeck and Holly Witteman are members of the Canadian Immunization Research Network (CIRN) a national network of vaccine researchers.
Elhadji Anassour Laouan Sidi
Elhadji Anassour Laouan Sidi, Denis Hamel, Maude Dionne and Dominique Gagnon are research professionals and statisticians at the National Institute of public health in Quebec.
Cornelia Betsch
Cornelia Betsch is Professor of Health Communication with a background in vaccine decision-making.
Stephan Lewandowsky
Stephan Lewandowsky is a cognitive scientist doing research to examine people’s memory, decision-making and knowledge structures.
Benjamin Malo
Benjamin Malo is a PhD student in anthropology. Mushin, Yesilada, is a PhD student in cognitive science.
Philipp Schmid
Philipp Schmid is a postdoctoral researcher studying the psychology of misinformation and science denialism.
Sander van der Linden
Sander L van der Linden is Professor of Social Psychology in Society. His research examines how people form judgments and decisions about societal issues.
Pierre Verger
Pierre Verger is a physician, epidemiologist and senior researcher doing research on vaccine hesitancy.