Conclusions
Health authorities around the world face an enormous challenge in increasing the uptake of COVID-19 (booster) vaccines. Research from cognitive and behavioral science can help to analyze the situation and design interventions that, ideally, boost trust, understanding, and intention. Our cross-sectional study suggests that vaccine-hesitant people might benefit more from interactive risk simulations than from text-based formats. There is no guarantee that this intervention will work in all contexts and under all conditions. More work on the underlying mechanisms is needed in order for the full potential of such simulations to be understood and harnessed. In future pandemics, interactive simulations that transparently communicate the benefits and harms of vaccination (and uncertainty where it exists) can be an important new instrument in the toolbox of health authorities seeking to overcome vaccine hesitancy and build public trust.