Why Collecting Health Data Hinges on Trust, Strategy, and Inclusion

by Jon Scaccia December 27, 2024

If asked to share a drop of your blood or a snippet of your health records for research, would you? Now, imagine being reassured that your data will improve healthcare for generations. Would you feel differently?

A recent study by our buddies at Centre for Addiction and Mental Health (CAMH) unveils surprising insights about what drives—or deters—our willingness to contribute to health research.

Unlocking Health Research: The Power of Biological Samples and Data Linkage

Health surveys form the backbone of public health policy, offering snapshots of community health trends. However, their potential is limited when researchers rely solely on self-reported data. Biological samples—like blood or saliva—and linked personal health information (PHI) can bridge this gap, painting a more accurate picture of population health. Yet, as the CAMH study highlights, asking for this data is far from straightforward.

In 2019, CAMH surveyed over 2,800 Ontarians, uncovering that only 36.2% were willing to provide saliva samples, and a mere 17% agreed to share their health insurance numbers for direct data linkage. Interestingly, 82.1% supported probabilistic linkage—an approach that anonymizes personal identifiers while connecting survey responses to health records.

This raises the question: What fuels our willingness—or reluctance—to share?

Understanding the Hesitation

The study revealed that willingness varies significantly based on demographics, mental health status, and even the order in which questions are posed. For example:

• Demographics Matter: Older adults (75+) were surprisingly more open to providing blood samples, while respondents with less education were less likely to agree to direct data linkage.
• Cultural Trust Gaps: People of non-White racial identities expressed less willingness to share saliva samples or participate in probabilistic linkage, echoing longstanding mistrust of health systems.
• Substance Use Nuances: Lifetime cocaine users were more open to sharing blood samples than those who had never used the drug, while individuals using non-medical opioids were more hesitant about direct linkage—likely due to fears of losing access to necessary medications.

These patterns suggest that participation isn’t just a matter of willingness but reflects a complex web of trust, education, and perceived risk.

The Question of Asking: Timing Matters

Beyond demographics, CAMH’s randomized trial showed that the sequence of questions dramatically impacts participation. When asked to provide a saliva sample first, respondents were more likely to agree compared to those asked for direct data linkage initially. Conversely, leading with a probabilistic linkage request made subsequent saliva sample requests less palatable.

This psychological effect, known as order bias, underscores how strategic survey design can nudge participants toward greater cooperation. But it also poses ethical challenges: How much persuasion is too much?

Real-World Implications

1. Boosting Consent Rates: Strategic question sequencing and clear communication about data use could dramatically increase participation. This is especially vital for surveys requiring biological samples, often labeled the “rate-limiting step” in research.
2. Closing Trust Gaps: Mistrust among minority groups and lower-educated respondents demands a proactive approach. Transparent policies, secure data practices, and culturally competent engagement are critical to ensuring equitable representation in research.
3. Future of Personalized Medicine: As the era of personalized medicine advances, linking biological and health data will be indispensable. These insights can illuminate the genetic and environmental underpinnings of diseases, paving the way for targeted interventions.

What’s Next?

The CAMH study opens the door to a series of critical questions:

• How can researchers effectively balance ethical persuasion with genuine consent?
• What steps are necessary to address mistrust in underrepresented communities?
• Could gamification, financial incentives, or community partnerships encourage broader participation?

Future studies should focus on:

• Exploring deeper motivations behind participation hesitancy.
• Developing tailored strategies for building trust with marginalized groups.
• Testing scalable solutions for ethical survey design that respects participant autonomy.

Join the Conversation

This study is more than an academic exercise—it’s a wake-up call for public health researchers and policymakers. Let’s turn these findings into action.

• How do you think public health researchers can build trust with communities reluctant to share data?
• Should incentives play a bigger role in encouraging participation? If so, what kind?
• What would make you feel comfortable sharing your own biological samples or personal health information for research?

Share your thoughts in the comments or join the conversation on social media using #HealthResearchMatters.

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