BACKGROUND AND OBJECTIVES: Vaccination is one of the most searched health topics online, yet the quality of resources varies considerably. This study evaluated the quality of Canadian COVID-19 vaccines online resources for caregivers of 5-11-year-old children. METHODS: We reviewed Canadian public-facing websites from academic pediatric hospitals, governments, professional organizations, and public health authorities until April 22, 2022. Inclusion criteria included English/French resources targeting caregivers of 5-11-year-olds, presented as webpages, FAQs, posters/infographics, and/or videos. Reliability, readability, and understandability/actionability were appraised using the JAMA Benchmark, Flesch-Kincaid Grade Level, and Patient Education Material Assessment Tool for Printable/Audiovisual materials, respectively. We used a content checklist to assess key vaccine topics (e.g., effectiveness and safety). Descriptive statistics included Fisher's exact and ANOVA tests. RESULTS: Of 1046 websites screened, 43 primary webpage clusters and 141 secondary webpages were analyzed. Twenty (46.5 %), 9 (20.9 %), 7 (16.3 %), and 7 (16.3 %) primary webpage clusters belonged to government, academic pediatric hospitals, professional organizations, and public health authorities, respectively. The mean JAMA Benchmark score was 3.47 ± 0.55 (out of 43). Of 43 clusters, only five (11.6 %) scored at or below a US 6th-grade education level. While 42/43 (97.7 %) primary clusters including printable materials were understandable (PEMAT-P >
70 %), only 7/43 (16.3 %) were considered actionable. The mean content score was 12.65 ± 3.60 (out of 20) among the 43 primary clusters. No differences in quality were seen across organization types, except for actionability (p = 0.016). CONCLUSIONS: Although most Canadian webpages on COVID-19 vaccines received high scores in understandability, areas requiring improvement in actionability, readability, and content were identified.