Funding for this research was provided by:
Wellcome Trust (200163/Z/15/Z)
Received: 21 February 2018
Accepted: 17 October 2018
First Online: 1 November 2018
Ethics approval and consent to participate
: Ethics approval for the analysis of the CIFT CRIS database was obtained from the National Research Ethics Service Committee East of England—Cambridge Central (14/EE/0177).This specific project was approved by the CIFT CRIS oversight committee following review of the study protocol.
: Not applicable.
: All authors have completed the ICMJE uniform disclosure form at ExternalRef removed and declare: GL2 was funded by a grant from the UK Department of Health, AS was funded by a fellowship from the Wellcome trust (200,163/Z/15/Z), and NW, GL1, GL2 and AS were supported by the University College London Hospitals National Institute of Health Research Biomedical Research Centre during the conduct of the submitted work. All authors declare no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
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