Funding for this research was provided by:
Canadian Institutes of Health Research (Fellowship Award, 133585, 133585, 133585)
Received: 6 June 2021
Accepted: 18 January 2022
First Online: 23 February 2022
: Ethical approval for this study and supporting material was received from the Hospital of Sick Children’s Research Ethics Board (Toronto, CANADA), Unity Health Toronto, and the respective participating school boards. Informed consent was obtained from the parents of participants.
: Not applicable.
: PCP reports receiving a grant from Hospital for Sick Children Foundation during the conduct of the study. PCP reports receiving the following grants unrelated to this study: a grant from Canadian Institutes of Health Research (FRN # 115059) for an ongoing investigator-initiated trial of iron deficiency in young children, for which Mead Johnson Nutrition provided non-financial support (Fer-In-Sol® liquid iron supplement) (2011-2017); and peer-reviewed grants for completed investigator-initiated studies from Danone Institute of Canada (2002-2004 and 2006-2009), Dairy Farmers of Ontario (2008-2010). JLM received an unrestricted research grant for a completed investigator-initiated study from the Dairy Farmers of Canada (2011-2012) and D drops provided non-financial support (vitamin D supplements) for an investigator-initiated study on vitamin D and respiratory tract infections (2011-2015). CMB reports previously receiving a grant for a completed investigator-initiated study from the SickKids Center for Health Active Kids (2015-2016) involving the development and validation of a risk stratification tool to identify young asymptomatic children at risk for iron deficiency. These agencies had no role in the design, collection, analyses, or interpretation of the results of this study or in the preparation, review, or approval of the manuscript. The other authors have no conflicts of interest to declare.