Received: 8 January 2018
Accepted: 18 June 2018
First Online: 3 July 2018
Ethics approval and consent to participate
: We obtained ethical approval for the study from the University of Johannesburg, Faculty of Health Sciences Research Ethics Committees (REC-241112-035).
: I confirm that all participant/personal identifiers have been removed so the patient/person(s) described are not identifiable and cannot be identified through the details of the study. Thus, consent for publication is not required.
: The authors declare that they have no competing interests.
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