An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Sikweyiya Y, Nduna M, Khuzwayo N, Mthombeni A, Mashamba-Thompson TP.Sikweyiya Y, et al.BMJ Open. 2016 Jun 13;6(6):e010154. doi: 10.1136/bmjopen-2015-010154.BMJ Open. 2016.PMID: 27297007Free PMC article.
Ntombela N, Mashamba-Thompson TP, Mtshali A, Voce A, Kharsany AB.Ntombela N, et al.Syst Rev. 2017 Jan 17;6(1):9. doi: 10.1186/s13643-016-0398-y.Syst Rev. 2017.PMID: 28095886Free PMC article.