MONTREAL — When communicating important public health messages, openly acknowledging uncertainty about the research supporting those messages can help foster trust and engagement, according to a poster presented at Public Health 2026, the annual meeting of the Canadian Public Health Association.

“We know through [the COVID pandemic] and the time since then that public trust [can drive] people to listen to our recommendations and then follow through on important public health behaviors and vaccinations,” study co-author Tyler Good, PhD, of the Behavioural Science Office at the Public Health Agency of Canada (PHAC), told Medscape News Canada. “We studied different ways we could frame uncertainty to see how they affected trust.”

Uncertainty Doesn’t Erode Trust

The investigators conducted an online survey from February 15 to March 10, 2025, of Canadian adults aged 18 years or older who were recruited via Qualtrics Online Panels. A total of 3668 participants completed the survey, and the group met preset quotas for demographic distributions of age, gender, and region based on the 2021 census. 

Participants were randomly assigned to one of two topics, either mpox or opioids and the drug crisis. Pre-survey questions assessed their demographics, baseline level of trust, and prior experience or beliefs about the topic.

Next, participants viewed a mock Facebook post. They were randomly assigned to view a message where standard information was presented with no uncertainty acknowledged, with uncertainty about the topic acknowledged, with uncertainty acknowledged and normalized, or with an explanation as to why uncertainty existed and what was being done to close the knowledge gap.

Participants then viewed a second Facebook post on the same topic but with a different type of uncertainty message from the one they originally saw. 

Finally, participants answered questions about their trust in government; in the messages they were shown; and in their attitudes, beliefs, and intended future behaviors related to the messages.

“We found no evidence that acknowledging uncertainty eroded trust, which I think is great news. Transparency is a foundational core value of public health institutions,” said Good. 

The message that fostered the most trust, engagement, and willingness to change behavior or learn more about the topic was the one that explained why the uncertainty existed and what was being done about it.

An exploratory analysis looking at predictors of people’s intentions to adhere to recommendations, even given uncertainty, found that three of the top four predictors were centered around science literacy, making that a key long-term target. The top three predictors were openness to evolving science, preference for information about uncertain science, and discernment of public health misinformation and disinformation.

How to Communicate Uncertainty

The authors offered the following advice for communicating uncertainty, based on their findings:

• It is generally better to communicate uncertainty than to not say anything. There may be an opportunity to build credibility through open communication, even as new evidence changes recommendations.
• Context matters, so it’s important to situate communications within public perceptions of urgency and relevance. Messages that feel less pressing may require more work to communicate effectively.
• When sharing recommendations, communicate openly about the work that supports them while still acknowledging limitations. This transparent approach may boost engagement.

For clinicians seeing patients, Good suggested that “there’s an opportunity to build credibility [and] do some science literacy building” by explaining to patients what the uncertainties are, why they exist, and what’s being done about them and giving suggestions on how to move forward.

This study was supported by the PHAC. Good reported having no relevant financial relationships.