Covid-19: contextualizing vaccination side effects can reduce concerns

Higher vaccination willingness through simple risk comparisons

They research team found that adding the “very low risk” label increased people’s intentions to take the vaccine by 3 percentage points as compared to the control group. Similarly, adding the comparison to motor vehicle death rates increased the willingness by 2.4 percentage points. These framing tools had even stronger effect when used together: the vaccine intentions were 6.1 percentage points higher. The effects did not differ by country, age or gender.

Comparing vaccine side-effect rates with Covid-19 death rates did not appear to influence vaccine intentions. The researchers had not expected this as Covid-19 death rates were substantially higher than motor vehicle death rates (170 per 100,000 versus 12 per 100,000 in the US) and as this cause of death is directly associated with the purpose of Covid-19 vaccination strategies.

“The study shows that even simple tools can increase trust in the safety of vaccines,” says lead author Nikkil Sudharsanan, a professor of Behavioral Science for Disease Prevention and Health Care at TUM. “The way risks are framed and presented to people can affect their perceptions of the severity of risk. Concern about side effects was heightened by widespread media coverage that did not put the very low risk in context with other risks. Comparing the risk of side effects with everyday risks could be a key component of efforts to improve vaccine use.”

“We believe our results can inform communication efforts aimed at increasing vaccination, especially booster vaccinations,” concludes co-author Alain Vandormael, Senior Data Scientist at the Heidelberg Institute of Global Health at UKHD. “Our results are focused on vaccine intentions and not vaccination rates, so the next step is to test whether these framing efforts can increase shots in arms before translating our findings into policy action.”