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.
Frank LD, Kuntz JL, Chapman JE, Fox EH, Dickerson JF, Meenan RT, Saelens BE, Young DR, Boone-Heinonen J, Fortmann SP.Frank LD, et al.BMC Public Health. 2019 Feb 15;19(1):200. doi: 10.1186/s12889-019-6518-6.BMC Public Health. 2019.PMID: 30770737Free PMC article.