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.
Chi I, Chou KL.Chi I, et al. Among authors: chou kl.Int J Aging Hum Dev. 2001;52(3):231-52. doi: 10.2190/V5K8-CNMG-G2UP-37QV.Int J Aging Hum Dev. 2001.PMID: 11407488