Received: 6 October 2017
Accepted: 11 March 2018
First Online: 21 March 2018
Ethics approval and consent to participate
: The study in its entirety including consent forms and all study materials was previously approved by the Health Research Authority (Integrated Research Application System (IRAS) ID: 219018) and the University Ethics Committee. All participants accepted anonymised use of their data for further analyses and subsequent publication during consent. Written consent was taken during recruitment.
: Not applicable.
: The authors declare that they have no competing interests.
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