Funding for this research was provided by:
National Institute for Health Research (RP-PG-0514-20015)
Received: 5 March 2020
Accepted: 8 June 2020
First Online: 30 July 2020
Ethics approval and consent to participate
: The study was approved by the University of Oxford Central University Research Ethics Committee [R56654/RE001]. Written informed consent was obtained from all study participants.
: Not applicable.
: The authors declare that they have no competing interests.