JMIR Publications

ABSTRACT

Background:

Vaccine hesitancy has been deemed one of the top ten threats to global health by the World Health Organization. Among the barriers to addressing vaccine hesitancy, anti-vaccine information on social media is concerning as people increasingly consult social media for health-related information. Understanding how vaccine proponents and opponents interact with each other on social media may help address vaccine hesitancy in various ways.

Objective:

This study aims to examine conversations between vaccine proponents and opponents on Reddit to understand whether online conversations truly provide a channel for the exchange of different points of view, whether people are able to communicate in an open and listening environment, and whether online conversations stimulate cognitive information processing.

Methods:

We analyzed large-scale conversational text data about human vaccines on Reddit from 2016 to 2018. Through machine learning and computer-assisted content analyses, we obtained each Redditor’s stance on vaccines, each post’s stance on vaccines, each Redditor’s language coordination score, and each post/comment’s analytical thinking score. We then performed statistical analyses to test the three questions of interest.

Results:

The results show that pro-vaccine and anti-vaccine Redditors are more likely to selectively reply to Redditors who share similar views on vaccines (p < .001). When Redditors interact with others who hold opposing views on vaccines, both pro-vaccine and anti-vaccine Redditors accommodate their language to the outgroup members (p < .05). Additionally, pro-vaccine and anti-vaccine Redditors do not show greater analytical thinking when interacting with outgroup members (p > .05), suggesting that Redditors do not engage in motivated reasoning when interacting with people who hold different stances on vaccines. Anti-vaccine Redditors on average have higher analytical thinking in the posts and comments compared to pro-vaccine Redditors (p < .001).

Conclusions:

This study shows though vaccine proponents and opponents selectively communicate with their ingroup members on Reddit, they accommodate their language and do not engage in motivated reasoning when they communicate with the outgroup members. The findings may shed light on the design of social-media-based pro-vaccine campaigns.