Accepted for/Published in: JMIR Human Factors
Date Submitted: Oct 22, 2025
Open Peer Review Period: Oct 24, 2025 - Dec 19, 2025
Date Accepted: Jan 20, 2026
(closed for review but you can still tweet)
Warning: This is an author submission that is not peer-reviewed or edited. Preprints - unless they show as "accepted" - should not be relied on to guide clinical practice or health-related behavior and should not be reported in news media as established information.
Developing an interactive, personalized patient decision aid for COVID-19 vaccination in Canada: Insights from a human-centered design and development study
ABSTRACT
Background:
The COVID-19 pandemic highlighted the need for practical digital health tools to support informed decision-making amidst rapidly evolving evidence and widespread misinformation.
Objective:
We iteratively developed and refined VaxDA-C19, a bilingual (English and French) web-based patient decision aid designed to support informed decision-making in Canada about COVID-19 vaccination. VaxDA-C19 integrates interactive and personalized features aimed to enhance vaccine confidence, reduce cognitive overload, and respond to diverse informational needs.
Methods:
We developed VaxDA-C19 using an iterative, user-centered design approach. Throughout the development process, we involved a citizen panel, healthcare professionals, user experience designers, and scientific experts to guide refinements. We also conducted usability testing sessions with adults in Canada, using semi-structured interviews, comparative testing, and think-aloud protocols with thematic analysis. We ultimately conducted four design cycles in total: three with adults in Canada (cycle 1: n=9 users; cycle 2: n=22 users; cycle 3: n=3 users), one overlapping and one additional cycle with expert reviewers (cycle 3: n=5; cycle 4: n=9).
Results:
In Cycle 1, user feedback guided design decisions about how to present quantitative information and technical vaccine descriptions more simply. In Cycle 2, while most users (82%) favored in-depth explanations of vaccine development, a few raised concerns about content that could be perceived as politically charged. Cycle 3 identified usability improvements, including more explicit navigation controls, simplified medical terminology, and optimized interactive components (avatars, sliders). Expert reviews in Cycle 4 refined linguistic consistency, mobile responsiveness, content transparency, and scientific accuracy, emphasizing explicit instructional guidance and bilingual accessibility.
Conclusions:
Our iterative process produced a personalized, bilingual digital decision aid to support evidence-informed, values-congruent decisions about COVID-19 vaccination. A randomized controlled trial will further evaluate VaxDA-C19's impact on vaccination intentions, knowledge retention, emotional responses, decisional conflict, and decisional regret. If it proves effective, the patient decision aid may also be used as a platform to support other vaccine decisions, namely, influenza, measles, shingles, pertussis, and potentially other emerging infectious diseases.
Citation
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Copyright
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