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.
Cinelli C, Pearl J.Cinelli C, et al. Among authors: pearl j.Eur J Epidemiol. 2021 Feb;36(2):149-164. doi: 10.1007/s10654-020-00687-4. Epub 2020 Oct 18.Eur J Epidemiol. 2021.PMID: 33070298