Funding for this research was provided by:
South African Medical Research Council
National Institute on Alcohol Abuse and Alcoholism (5R24AA022919-04)
National Research Foundation South Africa (SFH150722129394)
Received: 5 August 2018
Accepted: 26 November 2018
First Online: 7 December 2018
Ethics approval and consent to participate
: Ethics approval for this study was obtained from Stellenbosch University Health Research Ethics Committee (N16/02/026) and the University of Cape Town Human Research Ethics Committee (352/2016). Written informed consent was obtained. Participants were anonymised to protect their identities. No additional ethical concerns arose during the study.
: Consent for publication was included in the informed consent form.
: The authors declare that they have no competing interests.
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