Response to Felgendreff et al.

We thank Drs. Felgendreff and colleagues for their comments on our article. In our study, we found it important to look for ways of reducing optimistic bias (OB) to improve public engagement in COVID-19 preventive behavior/intentions. Educating and informing people of the real risk of contracting COVID-19 were suggested as a potential approach to contribute to this endeavor. Drs. Felgendreff et al. noted that their study results did not support this idea. That is, they revealed that reinforcing the actual risk of contracting COVID-19 did not reduce OB. We believe that their study findings add valuable empirical evidence to the literature. However, we would like to clarify some conceptual and methodological considerations about our study.

We conceptualize OB as a dispositional trait which is not transient and remains relatively stable throughout one's adult life.¹ This phenomenon may not suddenly appear or disappear within a day. Accordingly, to bring about changes in such bias, long-term continuous education and literacy programs through comprehensive efforts could be required. A one-time intervention may be insufficient to attenuate or eliminate the established bias. Periodic reinforcement of information can result in longer retention of the information.²

Our proposed study design differs from that of Dr. Felgendreff et al. Their study employed an experimental design comparing the prevalence of OB between one group who was informed of the risk of acquiring COVID-19 (treatment group) and another group who was provided information about preventive behaviors (control group). Exposure to information about preventive behaviors in the control group might confound the results by affecting the subjects' perceived risk of acquiring COVID-19. When people see, hear, and learn about preventive behaviors, they may feel that the corresponding health-related condition (e.g., COVID-19) is risky. Any COVID-19-related information might influence the subjects’ risk perception in the control group. In addition, this study did not include baseline levels of OB, and thus the results of intervention (i.e., changes in OB from the baseline levels) could not be determined. Accordingly, we propose a different study design to test our intended idea. Our original study found that optimistically biased individuals perceived their risk of getting infected with COVID-19 to be lower than that of their peers. As such, in our paper, we suggested that reinforcing the actual risk that applies to both self and peers could be helpful in reducing OB among these individuals. This suggestion was made based on our belief that once these individuals accurately realize their real risk, they would no longer misconceive their risk to be lower. In this sense, a pre and post analysis would offer an alternative study design to test the effects of an intervention on the changes of OB level among optimistically biased individuals. The intervention in this proposed study design can be aforementioned reinforcement of the actual risk that is similar to both self and others. Results from this within-subjects design will be able to show how their perceived risk for self and others might change after they realize their perceived risk to be different from the real risk that applies equally to both self and their peers. Through post-intervention testing, we would also measure whether the treatment group actually retains the intervention information (i.e., the real risk of acquiring COVID-19 for self and peers). Long-term follow-up of both the treatment and control groups would be desirable, evaluating whether they actually change their OB behavior. In particular, we would focus solely on individuals with high OB as a study population such as young people attending “coronavirus parties” and large crowds gathering during holiday weekends, as illustrated in our study.

We appreciate Drs. Felgendreff et al.’s efforts to address our suggestion. We hope that this discussion will prove helpful in designing future studies and interventions to reduce unrealistic optimism.

Declaration of competing interest

No funding has been received to conduct this study. No conflicts of interest exist.