Funding for this research was provided by:
Dunhill Medical Trust (R473/0216)
Received: 7 June 2019
Accepted: 27 January 2020
First Online: 4 March 2020
Ethics approval and consent to participate
: All participants gave written informed consent. Ethical approval was sought and granted from the University of Salford’s Ethics Committee (HSCR16/35, HSCR13/48) and the London Dulwich Research Ethics Committee (16/LO/0986).
: Not applicable.
: The authors declare that they have no competing interests.