Project title
Investigating intentions to get a coronavirus vaccine (Decoy study)
Research team
Aikaterini Grimani, Sandro Stoffel, Christian von Wagner, Aradhna Kaushal, Falko F Sniehotta, Ivo Vlaev
Main area of work
The aim of our study is to demonstrate the positive impact of adding a decoy option to a hypothetical vaccine invitation scenario. Specifically, the study will test whether offering individuals an additional less convenient vaccination appointment (decoy option) would increase the likelihood of individuals choosing the default vaccination appointment (target option).
Research question: Does adding a less convenient vaccination appointment to the choice set increase individuals’ intention to have the COVID-19 vaccination?
To answer this research question, we are proposing a prospective web-based study comprising three behavioural experiments to assess whether offering an additional decoy vaccination appointment increases people’s interest in having the COVID-19 vaccination. The fundamental idea underlying the decoy effect is that designing the decoy in such a way that it is only inferior to the target (standard vaccination appointment) but not the competitor (non-vaccination), it improves the perceived attractiveness of the target, thus increasing its likelihood to be chosen. Thus, offering an additional less attractive vaccination appointment should increase the attractiveness of the standard vaccination appointment, as human value judgments are relative and contextual (1). Three meta-analyses suggest that decoys can increase the likelihood of the target being chosen by 12 to 18% (2-4).
Publication information to follow.
Other work – sub-study:
Project title
The effect of communicating community immunity on COVID-19 vaccine hesitant people from ethnically diverse backgrounds: an experimental vignette study in the UK
Research team
Sandro T Stoffel, Aradhna Kaushal, Aikaterini Grimani, Christian von Wagner, Falko F Sniehotta and Ivo Vlaev
The primary aim of the this work was to explore how the framing of community immunity influences vaccination intentions among white and ethnic minorities. For this, we conducted a web-based experiment and recruited vaccine-hesitant individuals with a white ethnicity and an ethnic minority background. Specifically, we investigated whether the definition of the beneficiaries of community immunity affects vaccination intentions, expecting that highlighting the indirect effect of immunisation for the close social environment would increase intentions to get a COVID-19 vaccine. In line with previous research, we expect that the information about community immunity to be more effective in increasing vaccination intentions, if it mentions close social environments instead of overall society, as the definition of the beneficiaries influences social preferences. Additionally, the study also investigated whether communicating community immunity influences the perception of the vaccine in terms of social importance and expected uptake of peers.
A web-based experimental survey was used to assess how the framing of community immunity influences vaccination intentions. The survey was conducted in May 2021 and featured a sample of adult men and women who were invited to take part in an online survey on COVID-19 vaccination.
Publication from this work can be found here