Funding for this research was provided by:
National Research Foundation (107519)
South African Medical Research Council (9894)
Received: 7 March 2020
Accepted: 20 August 2020
First Online: 9 September 2020
Ethics approval and consent to participate
: None. The current study reports on publicly available data and no participant-level data were obtained.
: Not Applicable
: The authors have none to declare.