Abstract
Despite the importance of social network sites (SNSs) in addressing emerging public health risks, there is still a relative lack of studies examining the effects of risk communication via SNSs on risk perceptions and preventive behaviors. Based on message expression‒ and reception‒effects paradigms, this study aims to explore how expressing and receiving risk information shape preventive behavioral intentions via risk perceptions. Given the differential nature and functionality of SNSs, the present investigation also examines whether expressing and receiving risk information via two different types of SNSs—Facebook and Twitter—have different effects on risk perceptions and behavioral intentions. Analyzing survey data from 1,152 South Korean adults in the context of fine dust hazards, this study found that expressing and receiving risk information not only affected risk perceptions but also directly or indirectly influenced preventive behavioral intentions. In addition, the effects of expressing and receiving risk information were differentiated between SNS platforms, specifically Facebook and Twitter.