Funding for this research was provided by:
African Partnership for Chronic Diseases Research
South African Medical Research Council
Article History
Received: 26 December 2017
Accepted: 13 June 2018
First Online: 25 June 2018
Ethics approval and consent to participate
: Obtained from University of Cape Town, Human Research Ethics Committee Ref: 018/2016.
: Not applicable.
: Authors declare that they have no competing interests.
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