In this study, 2 684 people evaluated the credibility of two live web sites randomly assigned from one of 10 content categories. A total of 100 sites were assessed. The Stanford credibility team analysed the comments to discover how consumers evaluated credibility online.

They found that the average consumer paid far more attention to the look of a site than to its content. The team concluded that people first vet sites according to their design look. If a site passes the test, they then apply other criteria.

The tone of writing was something people used to assess credibility. Participant comments included writing time as a critierion 9.0 percent of the time, usually in a negative way. People generally said that slang or sensationalism hurt a site's credibility, while a straightforward, friendly writing style boosted credibility.

Stanford Web Credibility Research has the complete report (PDF, 1.2 MB, 105 pages).