People tend to perceive their own risk of contracting or passing on a disease as lower compared to the risk of similar others. 1 As one’s own perceived risk is a strong driver of protective behaviors, this so-called optimistic bias can undermine efforts to promote preventive behaviors in the current coronavirus pandemic. 2 Optimistic bias has been widely demonstrated during the coronavirus (COVID-19) pandemic, toward both the perceived risk of getting infected and that of infecting others. 3, 4 In their insightful article, Park et al.“suggest that by decreasing their perceived risk of getting infected […], optimistic bias can undermine individuals’ motivation to take precautions”(p. 1859). 5 As an intervention to reduce bias, they recommend, among other things, that reinforcing the actual risk of COVID-19 may be an effective intervention to attenuate the optimistic bias.

In a pre-registered experiment (see https://aspredicted. org/nx6ib. p d f), we tested whether presenting evidence-based information about the actual risk of COVID-19 can indeed reduce optimistic bias. The experiment was conducted as part of the cross-sectional COVID-19 Snapshot MOnitoring (COSMO) study series. 3 Ethical clearance was obtained from the University of Erfurt’s institutional review board (# 20200302/20, 200,501). In the last week of December 2020, N= 1006 individuals were recruited for a German non-probabilistic sample, quota-representative for age× gender and federal state. A total of 940 participants met the pre-registered age range (20–79 years of age) and stated that they had not been infected with COVID-19.