Funding for this research was provided by:
National Institute for Health Research (HPRU-2012-10141)
Received: 28 June 2017
Accepted: 9 April 2018
First Online: 24 April 2018
Ethics approval and consent to participate
: This project was evaluated and approved by the Faculty of Medicine and Health Sciences Research Ethics Committee from the University of East Anglia in Norwich, UK. The Research Ethics Committee reference number is 2016/17-101.
: Not applicable. This study does not include any individual person level data.
: The authors declare that they have no competing interests.
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