Life is fraught with hazards. However, the risk of many of these hazards can be reduced by performing protective behaviors. Acting appropriately to both stable and emerging or changing hazards requires humans to modify their protective behavior accordingly. It has been shown that risk perception is among the factors that are prerequisites for initiating protective behavior. Thus, when a new hazard emerges or the risk of a hazard changes, people presumably modify their risk perception accordingly, which in turn may promote the initiation of protective behaviors. This implies a dynamic interplay between risk, the perception of risk, and protective behaviors. The present dissertation aims at exploring aspects of this dynamic interplay for health risks.
The present dissertation first examined the association between health risk and risk perception. Three indicators of accuracy were examined for three infectious diseases, namely avian influenza, seasonal influenza, and the common cold. Specifically, conducting four cross-sectional surveys over a time period of 12 years showed that risk perceptions were concurrently accurate and inaccurate. While people held lower personal than general risk perceptions, indicating social inaccuracy (i.e., optimistic bias), the rank order between diseases was accurate at all four measurement points (i.e., general problem level accuracy), as people rated the risk for infection as highest for the common cold and lowest for avian influenza. Moreover, risk perceptions also accurately reflected the season and off-season times for seasonal influenza and common cold (i.e., dynamic problem level accuracy), although general risk perceptions reflected changes in the health risk to a greater extent. Thus, overall, people accurately modified their risk perceptions to changes in the general health risk.
The present dissertation then explored the relationship between health risk and protective behavior intentions. Specifically, it investigated whether increases in health risk were accompanied by increases in protective behavior intentions during the emerging phase of the Covid-19 pandemic in Germany. The analyses of three cross- sectional surveys indicated that intentions for social distancing and increasing personal hygiene increased in line with increases in health risk (i.e., total confirmed cases of Covid-19), whereas intentions to seek medical care increased at first but then decreased after the imposition of the lockdown in Germany. Moreover, small associations of age and intentions for protective behavior were revealed, which varied in accordance with the health risk. Specifically, age was positively associated with intentions for social distancing and personal hygiene in the early emergence of Covid- 19 in Germany, but this effect diminished after the imposition of the lockdown. However, a positive association of age and intention to visit a doctor only emerged after the imposition of the lockdown. Thus, people modified their protective behavior intentions as the health risk increased, and health risk moderated the small associations between age and protective behavior intentions.
Lastly, the interplay between protective behavior and risk perception in dependence of health risk was investigated. While the first two studies focused on infectious disease threats, the third study shifted the attention to noncommunicable diseases, specifically examining the interplay between self-reported healthy eating and diet-related risk perception in the context of providing personalized health feedback. Assessing the reciprocal relationship between self-reported healthy eating and diet- related risk perception for two groups of different feedback valence revealed relative and adaptive accuracy of perceived risk in both feedback groups. Specifically, people with higher perceived risk generally reported lower healthy eating (i.e., relative accuracy) and increases in self-reported healthy eating were followed by lower risk perception (i.e., adaptive accuracy). Thus, the same dynamic interplay between protective behavior and risk perception emerged for two degrees of health risk.
The findings of the present dissertation emphasize that people generally respond reasonably to changing health risks by modifying their risk perception and protective behavior intentions accordingly. Furthermore, the occurrence of changes in perceived risk after changes in self-reported protective behavior further highlights the dynamic nature of perceived risk. Overall, the findings of this dissertation provide an initial starting point for further research on the dynamic interplay between health risk, perceived risk, and protective behavior, to gain a more comprehensive understanding of the interactions between them. The further investigation of this interplay may contribute to a stronger focus on the reciprocal relationships between constructs and their dynamic interplay across time, which may foster the development of models and theories in health psychology that emphasize dynamics and reciprocal interrelations.