title: A comparison of world wide web resources for identifying medical information.
abstract: OBJECTIVE
  To compare the utility of a search engine, Google, with other medical and non-medical, web-based resources for identifying specific medical information.
  
  
  METHODS
  This institutional review board-approved case cross-over study randomly assigned 89 medical student volunteers to use either Google or any other web-based resource (excluding Google) to research 10 advanced medical questions in a multiple choice exam. Primary outcome measures were resource efficiency (inversely related to number of links used to identify the correct answer for each question) and correctness (number of correct answers/total number of questions answered). For Google searches, the sites providing the information in question were also evaluated.
  
  
  RESULTS
  The most frequently selected non-Google resources were Yahoo (n=531), Ask.com (n=110), and the interactive encyclopedia Wikipedia.com (n=74). Google was more efficient than all other resources (1.50 vs. 1.94 mean links, P<.0001), with no significant difference in correctness (97% [756/780] vs. 96% [747/780], P=.16). After a Google search, the four most common categories of sites that provided the correct answer were dictionary/encyclopedia sites, medical websites, National Library of Medicine resources, or journal websites. Yahoo was less efficient than Google (1.90 vs. 1.54 mean links, P<.0001). However, non-Google search engines were more efficient than web sites (eg, Wikipedia, medical websites) and PubMed (1.87 vs. 2.54 mean links, P=.0004).
  
  
  CONCLUSIONS
  Google is an efficient web resource for identifying specific medical information, by guiding users to an array of medical resources.
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, 601 N. Caroline Street, Room 3251, Baltimore, MD 21287, USA. Pjohnso5@jhmi.edu
authors.forename: Pamela T
authors.initials: PT
authors.lastname: Johnson
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Chen
authors.forename: John
authors.initials: J
authors.lastname: Eng
authors.forename: Martin A
authors.initials: MA
authors.lastname: Makary
authors.forename: Elliot K
authors.initials: EK
authors.lastname: Fishman
mesh_terms: D003625:Data Collection; D004526:Efficiency; D016247:Information Storage and Retrieval; D020407:Internet