Funding for this research was provided by:
Oak Foundation (n/a)
Received: 8 August 2019
Accepted: 21 January 2020
First Online: 21 February 2020
Ethics approval and consent to participate
: South-West Central Bristol Research Ethics Committee approved this study (13/SW/0012). All participants gave written consent to take part.
: All participants gave written consent for us to use quotations. We asked all participant for their consent to identify their role and participating site and gave the option of remaining entirely anonymous, which none took up.
: The authors declare that they have no competing interests.