Funding for this research was provided by:
National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care (NIHR CLAHRC) Greater Manchester
Received: 30 May 2017
Accepted: 15 December 2017
First Online: 18 January 2018
Ethics approval and consent to participate
: No ethical approval was needed for this paper, which does not us any personal data. Ethical approval was sought and granted, where appropriate, for the research projects which underpin the paper.
: Not applicable.
: The authors declare that they have no competing interests.
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