Funding for this research was provided by:
MRC/NIHR Methodology Research Panel (MR/NO15843/1)
Medical Research Council (MC_UU_12017/14)
Chief Scientist Office (SPHSU15, SPHSU14)
Medical Research Council (MC_UU_12017/15)
United Kingdom Clinical Research Collaboration (MR/KO232331/1)
Text and Data Mining valid from 2018-05-28
Received: 6 February 2018
Accepted: 7 May 2018
First Online: 28 May 2018
Ethics approval and consent to participate
: Not applicable.
: The authors declare that they have no competing interests.
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