Author Contributions: Dr De Wals had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: De Wals, Deceuninck, Toth, Boulianne, Landry, De Serres.
Acquisition of data: Deceuninck, Toth, Boulianne.
Analysis and interpretation of data: De Wals, Deceuninck, Brunet, Boucher, De Serres.
Drafting of the manuscript: De Wals, Deceuninck.
Critical revision of the manuscript for important intellectual content: De Wals, Deceuninck, Toth, Boulianne, Brunet, Boucher, Landry, De Serres.
Statistical analysis: Deceuninck.
Obtained funding: De Wals, Boulianne, De Serres.
Administrative, technical, or material support: De Wals, Deceuninck, Toth, Boulianne, Landry.
Study supervision: De Wals, De Serres.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr De Wals reports receiving research grants, honoraria, and reimbursements of travel expenses from vaccine manufacturers including GlaxoSmithKline, Novartis, Sanofi Pasteur, Merck, and Pfizer. Ms Boulianne reports receiving research grants from Sanofi Pasteur and GlaxoSmithKline. Dr De Serres reports receiving research grants from Sanofi Pasteur and GlaxoSmithKline. No other disclosures were reported.
Funding/Support: This study was funded by the Ministère de la Santé et des Services sociaux du Québec and by the Public Health Agency of Canada-Canadian Institutes for Health Research Influenza Research Network.
Role of the Sponsors: The sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation, review, and approval of the manuscript.
Additional Contributions: We thank all the health care professionals in Quebec who participated in the data collection.