Bias in comparisons of mortality among very preterm births: A cohort study

• Amélie Boutin ,

  Roles Conceptualization, Formal analysis, Writing – original draft, Writing – review & editing

  * E-mail: aboutin@bcchr.ca

  Current address: Department of Pediatrics, Université Laval, Reproduction, Mother and Youth Health & Population Health and Optimal Health Practices Units, CHU de Québec-Université Laval Research Center, Quebec City, Canada

  Affiliation Department of Obstetrics and Gynaecology, BC Children’s and Women’s Hospital and Health Centre, and the University of British Columbia, Vancouver, British Columbia, Canada

  https://orcid.org/0000-0003-1907-2920

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• Sarka Lisonkova,

  Roles Writing – review & editing

  Affiliation Department of Obstetrics and Gynaecology, BC Children’s and Women’s Hospital and Health Centre, and the University of British Columbia, Vancouver, British Columbia, Canada

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• Giulia M. Muraca,

  Roles Writing – review & editing

  Affiliations Department of Obstetrics and Gynaecology, BC Children’s and Women’s Hospital and Health Centre, and the University of British Columbia, Vancouver, British Columbia, Canada, Clinical Epidemiology Unit, Karolinska Institutet, Stockholm, Sweden

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• Neda Razaz,

  Roles Writing – review & editing

  Affiliation Clinical Epidemiology Unit, Karolinska Institutet, Stockholm, Sweden

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• Shiliang Liu,

  Roles Writing – review & editing

  Affiliation Maternal and Infant Health Section, Public Health Agency of Canada, Ottawa, Ontario, Canada

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• Michael S. Kramer,

  Roles Writing – review & editing

  Affiliation Departments of Pediatrics and of Epidemiology and Biostatistics, McGill University, Montreal, Quebec, Canada

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• K. S. Joseph

  Roles Conceptualization, Funding acquisition, Supervision, Writing – review & editing

  Affiliations Department of Obstetrics and Gynaecology, BC Children’s and Women’s Hospital and Health Centre, and the University of British Columbia, Vancouver, British Columbia, Canada, School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada

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