Received: 17 May 2019
Accepted: 22 July 2019
First Online: 29 July 2019
Ethics approval and consent to participate
: Research ethics were approved by the Research Ethics Committee of King’s College London Ethics Ref: LRS-17/18–4884. Written consent was obtained via the virtual learning environment.
: Not applicable. We confirm that participants gave written informed consent for the publication of anonymised quotations from their interview transcripts.
: There are no competing interests to declare.