Funding for this research was provided by:
Public Health Research Programme (13/99/32)
Received: 26 June 2017
Accepted: 20 May 2018
First Online: 28 June 2018
Ethics approval and consent to participate
: The University of Glasgow College of Social Sciences Ethics Committee (CSS/2011/029) gave ethical approval. All participants provided written informed consent.
: KH was Deputy Chair of the National Institute for Health Research Public Health Research Funding Board when the study was conducted.
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