Funding for this research was provided by:
National Institute for Health Research (BRC-1215-20008)
Received: 8 November 2017
Accepted: 22 May 2018
First Online: 1 June 2018
: Alastair Macfarlane MA, MBBS is an Academic Foundation Year 1 doctor working at the Royal Free Foundation Trust. He is currently working in psychiatry at the Springwell Centre, Barnet Hospital. Trisha Greenhalgh FMedSci is a GP and Professor of Primary Care Health Sciences at the University of Oxford.
: The authors declare that they have no competing interests.
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