Talking about Decisions: The Facilitating Effect of a Celebrity Health Announcement on the Communication of Online Personal Experiences around Decision-making

Platform Effects on Public Health Communication: A Comparative and National Study of Message Design and Audience Engagement Across Twitter and Facebook

BACKGROUND

Public health agencies widely adopt social media for health and risk communication. Moreover, different platforms have different affordances, which may impact the quality and nature of the messaging and how the public engages with the content. However, these platform effects are not often compared in studies of health and risk communication and not previously for the COVID-19 pandemic.

OBJECTIVE

This study measures the potential media effects of Twitter and Facebook on public health message design and engagement by comparing message elements and audience engagement in COVID-19-related posts by local, state, and federal public health agencies in the United States during the pandemic, to advance theories of public health messaging on social media and provide recommendations for tailored social media communication strategies.

METHODS

We retrieved all COVID-19-related posts from major US federal agencies related to health and infectious disease, all major state public health agencies, and selected local public health departments on Twitter and Facebook. A total of 100,785 posts related to COVID-19, from 179 different accounts of 96 agencies, were retrieved for the entire year of 2020. We adopted a framework of social media message elements to analyze the posts across Facebook and Twitter. For manual content analysis, we subsampled 1677 posts. We calculated the prevalence of various message elements across the platforms and assessed the statistical significance of differences. We also calculated and assessed the association between message elements with normalized measures of shares and likes for both Facebook and Twitter.

RESULTS

Distributions of message elements were largely similar across both sites. However, political figures (P<.001), experts (P=.01), and nonpolitical personalities (P=.01) were significantly more present on Facebook posts compared to Twitter. Infographics (P<.001), surveillance information (P<.001), and certain multimedia elements (eg, hyperlinks, P<.001) were more prevalent on Twitter. In general, Facebook posts received more (normalized) likes (0.19%) and (normalized) shares (0.22%) compared to Twitter likes (0.08%) and shares (0.05%). Elements with greater engagement on Facebook included expressives and collectives, whereas posts related to policy were more engaged with on Twitter. Science information (eg, scientific explanations) comprised 8.5% (73/851) of Facebook and 9.4% (78/826) of Twitter posts. Correctives of misinformation only appeared in 1.2% (11/851) of Facebook and 1.4% (12/826) of Twitter posts.

CONCLUSIONS

In general, we find a data and policy orientation for Twitter messages and users and a local and personal orientation for Facebook, although also many similarities across platforms. Message elements that impact engagement are similar across platforms but with some notable distinctions. This study provides novel evidence for differences in COVID-19 public health messaging across social media sites, advancing knowledge of public health communication on social media and recommendations for health and risk communication strategies on these online platforms.

How does information overload about COVID-19 vaccines influence individuals' vaccination intentions? The roles of cyberchondria, perceived risk, and vaccine skepticism

This research proposes and tests an integrated model to explain how information overload influence vaccine skepticism and vaccination intention. In addition, this research investigates the effectiveness of using a celebrity endorsement strategy in promoting vaccination and compares its effectiveness with other endorsement types. A survey study (Study 1) was conducted to examine the mechanism underlying the impact of the COVID-19 vaccine information overload on vaccine skepticism that, subsequently, affects vaccination intention. It also examined the moderating role of celebrity endorsement trustworthiness. The results indicate that information overload positively influenced vaccine skepticism through cyberchondria and perceived risk of the vaccine, which subsequently reduces vaccination intention. The negative effect of vaccine skepticism on vaccination intention was weakened by the celebrity endorsement that was considered trustworthy. A follow-up experimental study (Study 2) was performed to compare the effectiveness of celebrity endorsement with other endorsement types (i.e., government official and medical expert endorsements). The results showed that the celebrity endorsement was more effective in mitigating the negative effect of vaccine skepticism on vaccination intention compared to government official and medical expert. The findings provide practical insights into how governments can minimize people's vaccine skeptical views and increase their vaccination intentions.

Whose Tweets on COVID-19 Gain the Most Attention: Celebrities, Political, or Scientific Authorities?

Twitter has considerable capacity for health education and proves to be an efficient and accessible communication tool in the coronavirus disease-19 (COVID-19) pandemic. Although many stakeholders saturate Twitter with COVID-19-related information, it remains unknown who disseminates information most efficaciously. COVID-19-related tweets were obtained from Twitter accounts of health agencies, governmental authorities, universities, scientific journals, medical associations, and celebrities. Posts' impact was measured with the nominal and relative (%followers) number of likes and retweets. A sentiment analysis was conducted.We have identified 17,331 COVID-19-related tweets posted by 338 accounts in >4 months since the virus began to spread. The largest number of likes was received by tweets of celebrities (median nominal, relative likes; 14,918, 0.036 percent), politicians (259, 0.174 percent), and health agencies (231, 0.007 percent). Most retweeted messages were also posted by celebrities (2,366, 0.005 percent), health agencies (130, 0.004 percent), and politicians (55, 0.041 percent). Retweets and likes peaked in March 2020, and the overall sentiment of the tweets was growing steadily. Whereas celebrities and politicians posted positive messages, the scientific and health authorities often employed a negative vocabulary. The posts with positive sentiment gained more likes and relative likes than nonpositive. During the pandemic, the tweets of celebrities and politicians related to COVID-19 outperform those coming from health and scientific institutions. Active engagement of Twitter influencers may help key messages go viral.