Funding for this research was provided by:
MRC North West Hub for Trials Methodology Research (MR/K025635/1)
Received: 28 September 2018
Accepted: 29 January 2019
First Online: 11 February 2019
: Full details provided on page 1.
: The University of Liverpool Ethics Committee was consulted and granted ethical approval for both the Delphi survey (Reference 2232) and the consensus meeting (Reference 3271). Informed consent was assumed if a participant responded to the Delphi survey or agreed to attend the consensus meeting.
: Not applicable.
: DGA, JMB, MC, ST and PRW are members of the COMET Management Group. SG and JJK declare that they have no competing interests.
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