Funding for this research was provided by:
Medical Research Council (MC/PC/15030)
Received: 7 October 2019
Accepted: 4 November 2019
First Online: 21 November 2019
Ethics approval and consent to participate
: The study, performed between September 2017 and August 2018, complied with the Declaration of Helsinki and obtained a favourable opinion from the Newcastle and North Tyneside 1 Research Ethics Committee (206363, 16/NE/0299) and the Health Research Authority, with the parents/carers of the subjects giving written informed consent, and written assent from the young people.
: Consent for the publication of anonymised participant study results and images was obtained from all participants as part of the study consent process above.
: The authors declare that they have no competing interests.