Funding for this research was provided by:
Medical Research Council (MC_UU_12015/3)
Received: 5 June 2020
Accepted: 3 August 2020
First Online: 12 August 2020
Ethics approval and consent to participate
: Ethical approval to conduct the study was obtained from the ethical boards at each study site. Informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.