Article History
Received: 8 December 2017
Accepted: 2 February 2018
First Online: 14 February 2018
Compliance with ethical standards
:
: On behalf of all authors, the corresponding author states that there is no conflict of interest.
: This study was approved by the University of Cape Town Human Research Ethics Committee (HREC REF: 131/ 2009). Study participants were 18 years and older, and written informed consent was sought before data collection.