Quality of health and medical information on the Internet.

This article examines some of the problems associated with health and medical information available via the Internet. An overview is provided of gateway services that seek to provide access to high quality materials. Quality principles for health and medical Internet-based materials are highlighted and suggestions are offered for evaluating sources of information retrieved via the Internet. The article concludes that, although there is undeniably a vast quantity of useful material available via the Internet, the principles of basing health care on the best available evidence still apply and potential users need to critically appraise any information they wish to use.