Funding for this research was provided by:
Economic and Social Research Council (ES/J500094/1)
Article History
Received: 13 December 2017
Accepted: 6 December 2018
First Online: 7 January 2019
Ethics approval and consent to participate
: Ethical approval was gained from the University of Liverpool Ethics Sub-committee (IPHS-1213-LB-064) and the study was performed in accordance with the ethical standards laid down in the Declaration of Helsinki. Prior to participation, informed written consent was gained from each subject.
: Not applicable
: The authors declare that they have no competing interests.
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