Funding for this research was provided by:
Received: 21 August 2017
Accepted: 1 February 2018
First Online: 1 March 2018
Ethics approval and consent to participate
: The study was approved by the Science, Technology, Engineering and Mathematical Ethical Review Committee at the University of Birmingham. Parents provided written consent on behalf of all children as they were aged under 16. Children with the capacity to assent also completed an assent form.
: Not applicable
: The authors declare that they have no competing interests.
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