Funding for this research was provided by:
National Institute for Health Research (NIHR CLAHRC East Midlands)
Received: 2 October 2018
Accepted: 7 January 2019
First Online: 23 January 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the National Research Ethics Service London – Riverside Committee (reference 14/LO/1102). All participants gave written informed and oral consent to the study, directly to a member of the research team.
: Not applicable.
: The authors declare that they have no competing interests.
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