Funding for this research was provided by:
School for Public Health Research (NU-004252)
Nuffield Foundation (WEL/FR-000022583, WEL/FR-000022583, WEL/FR-000022583)
Wellcome Trust (221400/Z/20/Z, 205407/Z/16/Z)
Received: 7 May 2021
Accepted: 29 November 2021
First Online: 15 December 2021
: Ethical approval to conduct the study was granted by the University College London research ethics committee (Project ID: 14895/005). All participants provided written informed consent to take part in the study.
: Not applicable.
: The author(s) declare no competing interests with respect to the research, authorship and/or publication of this article.