Funding for this research was provided by:
South African Medical Research Council (SIR McGaw)
National Research Foundation (Incentive Funding)
Text and Data Mining valid from 2019-05-22
Received: 14 July 2018
Accepted: 9 May 2019
First Online: 22 May 2019
Ethics approval and consent to participate
: No ethics approval was required because no experiments on humans or animals were carried out.
: Not applicable.
: The authors declare that they have no competing interests.
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