Corresponding Author: Sarah A. Buchan, PhD, Public Health Ontario, 661 University Ave, Floor 17, Toronto, ON M5G 1M1, Canada (sarah.buchan@oahpp.ca).
Accepted for Publication: May 19, 2021.
Published Online: August 16, 2021. doi:10.1001/jamapediatrics.2021.2770
Correction: This article was corrected on September 20 2021, to fix a typo in Table 2.
Author Contributions: Ms Paul and Dr Buchan had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Concept and design: Paul, Daneman, Schwartz, Science, Brown, Buchan.
Acquisition, analysis, or interpretation of data: Paul, Schwartz, Science, Brown, Whelan, Chan, Buchan.
Drafting of the manuscript: Paul.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Paul, Schwartz, Brown.
Administrative, technical, or material support: Paul, Schwartz, Buchan.
Supervision: Science, Buchan.
Conflict of Interest Disclosures: Dr Buchan reported grants from Canadian Institutes of Health Research for research on influenza, respiratory syncytial virus, and COVID-19 and grants from Canadian Immunity Task Force for COVID-19 vaccines outside the submitted work. No other disclosures were reported.
Funding/Support: This study did not have a direct funding source but was supported by Public Health Ontario.
Role of the Funder/Sponsor: The sponsor had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Additional Contributions: We thank James Johnson, MPH, and Arezou Saedi, MD, for conducting the address-matching work; Trevor van Ingen, MPH, for providing the neighborhood-level data; and Semra Tibebu, MPH, for cleaning the individual-level household size variable. These individuals made their contributions as part of their roles as paid employees of Public Health Ontario at the time of the study.
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