Optimistic bias about H1N1 flu: testing the links between risk communication, optimistic bias, and self-protection behavior.

Using two-wave panel survey data (N = 348) collected in South Korea in the context of H1N1 flu, we explored several important aspects of optimistic bias that have been relatively unexplored in previous research, including: (a) the extent to which risk communication and indirect risk experience affect changes in optimistic bias over time; (b) the utility of the concept of optimistic bias to predict subsequent risk behavior; and (c) how optimistic bias moderates the effect of risk communication and indirect risk experience on self-protection behavior. The findings revealed that optimistic bias is rather enduring and resilient, as it changed only under one condition (high indirect risk experience combined with low interpersonal communication). Optimistic bias had a nonsignificant association with self-protection behavior, but played an important moderating role by reducing the effect of interpersonal communication on self-protection behavior.