Funding for this research was provided by:
Canadian Institutes of Health Research (107535)
Received: 22 June 2018
Accepted: 10 October 2018
First Online: 22 October 2018
Ethics approval and consent to participate
: The Clinical Research Ethics Boards at the University of British Columbia approved all procedures (certificate H14–01572).
: Parents or guardians provided written informed consent and children provided assent.
: The authors declare that they have no competing interests.
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