Funding for this research was provided by:
Medical Research Council (1310277)
Received: 28 July 2017
Accepted: 16 February 2018
First Online: 27 February 2018
Ethics approval and consent to participate
: Ethical approval was granted by the University of Glasgow, College of Social Sciences Research Ethics Committee (CSS201020106), which complies with the UK Economic and Social Research Council’s Framework for Research Ethics. All participants provided informed consent to take part in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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