Funding for this research was provided by:
Cancer Research UK (C1483/A18262)
Received: 5 December 2018
Accepted: 25 June 2019
First Online: 9 July 2019
Ethics approval and consent to participate
: The study received ethical approval from North West - Greater Manchester East Research Ethics Committee (14/NW/1449).
: Not applicable
: The authors declare that they have no competing interests.