Funding for this research was provided by:
Medical Research Council
Received: 13 March 2018
Accepted: 4 July 2018
First Online: 13 July 2018
Ethics approval and consent to participate
: This study was approved by the South Birmingham Local Research Ethics Committee 10/H1206/58. Written informed consent was obtained from all of the patients.
: This is not applicable for this study.
: The authors declare that they have no competing interests.
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