Quality of breast cancer sites on the World Wide Web.

The Internet is a powerful tool for accessing information about complex health topics. The purpose of this study was to evaluate breast cancer Internet sites using published criteria about website structure. Two searches were undertaken (November 1998 and June 1999) using the Yahoo search engine, providing a sample of 136 unique addresses. The results showed 1) owner's credentials were identified in 31.6% of sites, 2) financial charges were stated in 10.3% of sites, 3) less than 14.0% identified site creation date, 4) 33.1% identified content posting update, 5) 30.1% identified information sources, and 6) just under 88% of sites provided e-mail interactivity. The results indicate variability in breast cancer Internet sites with respect to framework criteria of accountability. We suggest that websites that lack fundamental indicators (such as dating and sources) do not provide the user with fundamental information that could enable informed decision making about site quality.