Funding for this research was provided by:
National Institute for Health Research
Cancer Research UK
Received: 30 September 2018
Accepted: 26 December 2018
First Online: 8 January 2019
Compliance with ethical standards
: All procedures performed in the study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.. All participants gave informed written consent for inclusion in the study.