Ratios of Trust: the Rise and Fall of the WHO’s Popular Legitimacy

In the digital age, a ratio on social media is more than just a fleeting moment of internet drama, it can be a measurable signal of institutional trust. As global health crises like COVID-19 unfold, the battle for public confidence moves from official press releases to the real-time arena of social platforms. But can we scientifically measure something as complex as popular legitimacy simply by looking at how the world interacts with an organization on X?

Christiane Melchior, a postdoctoral researcher at Lappeenranta-Lahti University and her colleagues from the Université de Montréal, has pioneered a way to do exactly that. In their recent study, "Social Media Metrics and Popular Legitimacy: Content Analysis of Pre- and Post-COVID-19 Public Engagement With the World Health Organization on X," published in the Journal of Medical Internet Research, they introduced a framework that turns digital engagement into a barometer for global health governance.

Moving Beyond Likes and Shares

While many social media strategies focus on raw reach, Melchior’s research looks at the quality of the interaction. By analyzing 46,667 tweets from the World Health Organization (WHO) spanning a 13-year period (2008–2021), the team identified a critical indicator: the retweet-to-reply ratio.

The logic is simple but powerful:

• Retweets generally signal endorsement and a willingness to spread a message.
• Replies on institutional accounts often signal dissent, scrutiny, or controversy.
• A higher retweet-to-reply ratio can be interpreted as more supportive engagement, and a lower ratio as more public skepticism.

The research found that the WHO’s popular legitimacy remained remarkably stable for over a decade. However, the onset of the COVID-19 pandemic triggered a game-changing shift. As tweet frequency surged, the ratio of retweets to replies plummeted, signaling a sustained decline in public confidence that lasted through 2021.

The Infodemiology Frontier

This study sits at the cutting edge of infodemiology, which is the science of how health information spreads, what influences it, and its impact on public health. Melchior notes that global crises fundamentally shift how the public views international institutions. By tracking these digital signals, leaders can move beyond anecdotal evidence to monitor their reputation in real-time.

The practical implications are clear: global health leaders can use this ratiometric framework to adapt communication strategies dynamically. If engagement acceleration slows or replies begin to dominate the narrative, it serves as an early warning system to fight misinformation and rebuild trust before the damage to institutional authority becomes permanent.

Why JMIR?

Melchior and her colleagues chose to publish in the Journal of Medical Internet Research because of its status as the gold standard for research at the intersection of social media and public health. As a pioneer in open access, JMIR ensures that these findings reach the policymakers and practitioners who need them most to navigate future global health revolutions.

Curious to see how social media metrics can predict the rise and fall of institutional trust? Watch the video featuring Christiane Melchior and read the full research article to explore the ratiometric framework used to analyze the WHO’s digital legitimacy.

Please cite as:
Warin T, Melchior C, de Marcellis-Warin N. Social Media Metrics and Popular Legitimacy: Content Analysis of Pre– and Post–COVID-19 Public Engagement With the World Health Organization on X. J Med Internet Res 2025;27:e69959
URL: https://www.jmir.org/2025/1/e69959
DOI: 10.2196/69959