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.
Rahi JS, Cable N; British Childhood Visual Impairment Study Group.Rahi JS, et al.Lancet. 2003 Oct 25;362(9393):1359-65. doi: 10.1016/S0140-6736(03)14631-4.Lancet. 2003.PMID: 14585637