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.
Howell P, Davis S, Au-Yeung J.Howell P, et al.Child Lang Teach Ther. 2003 Oct 1;19(3):311-337. doi: 10.1191/0265659003ct257oa.Child Lang Teach Ther. 2003.PMID: 18259597Free PMC article.