Correcting public misperceptions about medical doctors' opinions persistently increases Covid-19 vaccinations

Identifying sources of vaccine hesitancy and ways how to reduce it has been one of the central public policy challenges during the COVID-19 pandemic. We show that public misperceptions about doctors' views on Covid-19 vaccinations reduce willingness to get vaccinated. Specifically, we document three observations: (1) The vast majority of medical doctors in the Czech Republic trust and support vaccination. (2) There is a widespread belief among the public that doctors’ opinions are divided and that only about half trust the vaccines. (3) Informing people that there is a broad positive consensus among doctors persistently increases vaccination uptake by the public. Thus, effectively communicating doctors‘ true views can play an important role in the fight against the Covid-19 pandemic.

Our focus on public misperceptions of the views of doctors is motivated by a widespread concern that media coverage can create uncertainty and polarization in how people perceive expert views, even when a broad consensus actually exists. In terms of traditional media, a desire to appear neutral often motivates journalists to provide a ‘balanced’ view by giving roughly equal time to both sides of an argument creating an impression of controversy and uncertainty. Such ‘falsely balanced’ reporting has been shown to be a characteristic element of policy debates ranging from climate change to health issues. In the context of the COVID-19 vaccines, casual observation suggests that media outlets often feature expert opinions that highlight the efficacy of approved COVID-19 vaccines together with skeptical experts who voice concerns about rapid vaccine development and untested side effects.

In order to learn more about opinions among wider medical community and how they can affect willingness of the public to get vaccinated, we proceed in three steps. In the first step, we wanted to find out what the medical community really thought about vaccinations at the time the newly approved vaccines were about to go into wide circulation. In February of 2021, we implemented a short online survey among 9,650 doctors in the Czech Republic in cooperation with the Czech Medical Chamber. We found strong evidence of consensus: 90% of doctors intended to get vaccinated themselves and 89% trusted the approved vaccines.

Step two was to find out what were people’s beliefs about doctors’ trust in the vaccines. We asked a sample of more than 2,000 people participating in an online survey which was designed to be representative of the adult population in the Czech Republic. We found evidence of systemic and widespread misperceptions of the views held by the medical community: more than 90% of people underestimated doctors’ trust in the vaccines and their vaccination intentions, with most people believing that only 50% of doctors trust the vaccines and intend to be vaccinated. So - people thought that there was controversy among doctors about vaccination, that the approval rate was about half and half, that even the professional community did not really agree on it. While, in fact, most doctors agreed.

These findings set the stage for the third step - the main experiment. What happens when people get information that the experts are in agreement? Will it change their opinion? And in the case of vaccination it was even possible to observe the effects on people’s behavior. Did they then get vaccinated?

In March 2021, a randomly selected half of the respondents received correct information about the opinions of doctors about vaccination, i.e., that 90% trust the vaccines. The other half of the respondents did not receive this information. This allowed us to reliably estimate the role that knowledge of the real views of the medical community plays in the willingness to be vaccinated. For the next nine months, we regularly surveyed the respondents to see if they got vaccinated. The information provided reduced misperceptions about doctors' views on vaccination, but also increased vaccination uptake by 4.5 percentage points. Put differently, the percentage of people who chose not to be vaccinated therefore fell by as much as 20%. Interestingly, the effect on vaccination was stable and lasting. Even a one-time provision of information increased vaccination uptake for at least nine months and also increased demand for the third dose of the vaccine.

What are the implications? First, the data tell us how distant public opinion can become from reality, but also how cheap it can be to correct misperceptions when people learn through a simple information campaign that most experts actually agree on something. Second, professional associations can serve as aggregators of views of individual experts and the resulting data can be provided to the public in the form of simple statistical facts. Third, although we cannot empirically pin down the sources of the misperceptions observed in our study, we suspect that they originate, at least in part, in a journalistic norm in which balance is often considered a mark of objective and impartial reporting, and a way to attract the attention of news consumers. Our results suggest that it would be useful if media, when presenting discussions between experts with opposing views, provided information about how prevalent such views are among wider expert community.

Finally, the inaccurate public perceptions that experts are divided, despite the fact that a broad consensus in fact exists, is likely relevant in a number of other areas, such as the climate change debate, and it may undermine the societal support required to solve fundamental national and global problems. Thus, the lessons from this study likely apply to a number of other issues, and the Covid-19 pandemic might be just one example of a more general phenomenon.

Original research paper: Bartoš, Vojtěch, Michal Bauer, Jana Cahlíková and Julie Chytilová (2022): Communicating doctors’ consensus persistently increases Covid-19 vaccinations. Nature 606: 542-549.