Funding for this research was provided by:
National Institute for Health Research (HCS DRF-2014-05-002)
Text and Data Mining valid from 2018-05-08
Received: 16 March 2018
Accepted: 27 April 2018
First Online: 8 May 2018
Ethics approval and consent to participate
: Ethical approval was granted by City and East Research Ethics Committee for use of historical patient data in this study (study number 15/LO/0736). As this was a retrospective study, informed consent was not required.
: The authors declare that they have no competing interests.
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