Funding for this research was provided by:
Health Technology Assessment Programme (12/167/102)
Received: 14 February 2018
Accepted: 17 January 2019
First Online: 8 February 2019
Ethics approval and consent to participate
: Ethical review and approval was provided by South Central - Oxford C Research Ethics Committee. The Confidentiality Advisory Group (CAG) gave approval for enrolment of patients without prior consent.
: Not applicable.
: The authors declare that they have no competing interests.
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