Funding for this research was provided by:
National Research Foundation (TTK13070720678)
Text and Data Mining valid from 2018-05-15
Received: 9 June 2017
Accepted: 19 April 2018
First Online: 15 May 2018
Ethics approval and consent to participate
: The North-West University Health Research Ethics Committee (HREC) approved the research presented in this paper. (Ethics permission number NWU 00002-16-A1).
: The authors declare that they have no competing interests.
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