BACKGROUND: In 2000, 41 million @entity1 searched for medical information online. The quality of that information is unregulated, variable, and not well studied. OBJECTIVE: To quantify and compare the numbers and types of Internet sites matched for 10 diverse @entity272 through different search systems. DESIGN: Search strategies were performed at 6-month intervals via Netscape Navigator, using 3 search engines and 1 directory. Ten @entity272 were chosen to represent common ( @entity1569 and @entity484 ), cosmetic (wrinkles and cellulite), difficult-to-treat ( @entity1665 , @entity5310 , @entity738 annulare, and @entity4741 ), and uncommon ( @entity14086 and @entity2640 ) problems. Search strings were designed to generate lists of Web sites that provide educational or product-related information. Results were compared. SETTING: The Saint Louis University information technology server, July 9, 1999, December 16, 1999, and February 5, 2000. MAIN OUTCOME MEASURES: Comparisons of the total number, top 10 ranking, and type (educational vs product-related) of sites that matched through different search systems at 6-month intervals. RESULTS: The total number of matched sites for different @entity272 varied up to 100-fold. This number increased by 30% to 316% between July and December 1999. The largest number of Web sites related to wrinkles, followed by Web sites related to common conditions. Product-related sites outnumbered educational sites, especially for common and cosmetic conditions. Although there were differences in the total number of sites found through different search engines, the ratios of product-related to educational sites were similar. Different search engines yielded different top 10 match lists for the same condition. The top 10 lists included higher proportions of educational sites than the total match lists for all conditions except cellulite. Within the top 10 lists, the rank order of well respected sites varied by search engine used and changed over time. CONCLUSIONS: @entity1 are increasingly accessing the growing body of data available through the Internet. Most Web sites contain information related to products. Until standards are enacted to govern the distribution of online medical information, consumers are at risk for obtaining misinformation and buying ineffective products. To better guide @entity1 , physicians must become familiar with this ever-changing information.

Product-related emphasis of XXXX information online.

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients', 'people'] @entity1665 :: ('MESH:D000505', 'Disease') :: ['alopecia'] @entity1569 :: ('MESH:D011565', 'Disease') :: ['psoriasis'] @entity5310 :: ('MESH:D008415', 'Disease') :: ['mastocytosis'] @entity738 :: ('MESH:D006099', 'Disease') :: ['granuloma'] @entity14086 :: ('MESH:D003874', 'Disease') :: ['dermatitis herpetiformis'] @entity2640 :: ('MESH:D004820', 'Disease') :: ['epidermolysis bullosa'] @entity4741 :: ('MESH:D014973', 'Disease') :: ['xanthoma'] @entity272 :: ('MESH:D012871', 'Disease') :: ['skin conditions'] @entity484 :: ('MESH:D004485', 'Disease') :: ['eczema']
@entity272 :: (MESH:D012871,Disease) :: ['skin disease']
