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.
Levy BS, Harris JC, Smith JL, Washburn JW, Mature J, Davis A, Crosson JT, Polesky H, Hanson M.Levy BS, et al. Among authors: smith jl.Am J Epidemiol. 1977 Oct;106(4):330-5. doi: 10.1093/oxfordjournals.aje.a112469.Am J Epidemiol. 1977.PMID: 333905
Denes AE, Smith JL, Maynard JE, Doto IL, Berquist KR, Finkel AJ.Denes AE, et al. Among authors: smith jl.JAMA. 1978 Jan 16;239(3):210-12.JAMA. 1978.PMID: 579391