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.
Norman R, Barnes B, Mathee A, Bradshaw D; South African Comparative Risk Assessment Collaborating Group.Norman R, et al.S Afr Med J. 2007 Aug;97(8 Pt 2):764-71.S Afr Med J. 2007.PMID: 17952235
Norman R, Mathee A, Barnes B, van der Merwe L, Bradshaw D; South African Comparative Risk Assessment Collaborating Group.Norman R, et al.S Afr Med J. 2007 Aug;97(8 Pt 2):773-80.S Afr Med J. 2007.PMID: 17952236
Barnes BR.Barnes BR.Int J Environ Res Public Health. 2014 Apr 25;11(5):4607-18. doi: 10.3390/ijerph110504607.Int J Environ Res Public Health. 2014.PMID: 24776723Free PMC article.Review.
Naicker N, Mathee A, Barnes B.Naicker N, et al.Epidemiology. 2013 Jul;24(4):621-2. doi: 10.1097/EDE.0b013e318296c077.Epidemiology. 2013.PMID: 23732739No abstract available.