Funding for this research was provided by:
Research Trainees Coordinating Centre (NIHR-CDF-2012-05-126)
Received: 4 March 2019
Accepted: 9 May 2019
First Online: 31 May 2019
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki. Ethical permission was granted by the West of Scotland Research Ethics Committee (14/WS/0090) and the University of Liverpool REC (IPHS-14145-040). Written informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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