Funding for this research was provided by:
Health Technology Assessment Programme (11/36/33)
Received: 8 March 2018
Accepted: 22 November 2018
First Online: 10 December 2018
Ethics approval and consent to participate
: This research was performed in accordance with the Declaration of Helsinki. Informed consent was provided by the patients or by consultee agreement/nearest relative, guardian or welfare attorney (Scotland) prior to the commencement of the study. Ethics approval has been granted by NRES Committee Yorkshire & The Humber - Leeds West; approved 17 April 2013; (REC reference: 13/YH/0066), and Scotland A Research Ethics Committee; approved 21 July 2014; (REC reference: 14/SS/0079).
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.