They liked and shared: Effects of social media virality metrics on perceptions of message influence and behavioral intentions

The present study examined the effects of social media virality metrics on perceptions of message influence on the self and others and intentions to take preventive actions. In an online experiment, a Facebook post about the topic of health risk was shown with the variations of virality metrics including the number of likes and shares. Overall, findings demonstrated the differential effects played by these virality metrics. Results revealed that high shares increased not only perceptions of message influence on the self and others but also preventive behavioral intentions. The mediation analysis indicated that share had an indirect effect on behavioral intentions through the perception of message influence on the self. A significant interaction effect between like and share was also found, such that the presence of high likes increased the third-person perception only when the message had low shares. Implications of these findings are further discussed with regard to leveraging the ability of virality metrics in health promotion practices on social media.