Funding for this research was provided by:
University of York/Health eResearch Centre (PhD2016PP2)
Accepted: 3 February 2021
First Online: 8 April 2021
: The BiB data requested are sensitive personal data. BiB received ethical approval for the data collection from the Bradford Research Ethics Committee (Ref 07/H1302/112), which included specifying the requirement for informed consent to participate (for the mothers) and informed consent from legal guardians (for the children). The planned study received ethical scrutiny as part of the BiB data application, and adhered to the 1964 Helsinki declaration and subsequent amendments. No further ethical approval was required for the analysis of the data (decision confirmed in writing by the Chair of the University of York Health Sciences Department Research Governance Committee)as pseudonymised existing data were used and we complied with all standards and policies of the University of York’s Data Management Policy (University of York Information Services, 2018).
: Consent obtained during recruitment to the Born in Bradford study, as outlined in the Ethics approval declaration.
: The authors declare that they have no competing interests.