Funding for this research was provided by:
Received: 12 December 2019
Accepted: 3 July 2020
First Online: 14 July 2020
Ethics approval and consent to participate
: A positive ethical opinion was received from The National Research Ethics Service (NRES) Committee London—Camden & Kings Cross (reference 15/LO/0674). Written informed consent to participate was obtained from participants for the VOLUME trial, which also included this interview study.
: Not applicable.
: None to declare.