From: "Jim Henderson, Mr." <[log in to unmask]> Date: Wed, 12 Sep 2012 15:15:22 +0000 There is a recent article on this topic: Nourbakhsh E, Nugent R, Wang H, Cevik C, Nugent K. Medical literature searches: a comparison of PubMed and Google Scholar. Health Info Libr J. 2012 Sep;29(3):214-22. Here is a PubMed link, which also provides related articles and a link to full text for those with access to Wiley journals: http://www.ncbi.nlm.nih.gov/pubmed/22925384 The authors found that: “PubMed searches and Google Scholar searches often identify different articles. In this study, Google Scholar articles were more likely to be classified as relevant, had higher numbers of citations and were published in higher impact factor journals. The identification of frequently cited articles using Google Scholar for searches probably has value for initial literature searches.” Subsequent discussion on the medical library listserv (medlib-l; some feel for the discussion here, found via Google - http://thlibrary.wordpress.com/2012/09/06/googlevspubmed/) revealed that the article may actually be a comparison of free text searching (the Google Scholar search) vs. controlled vocabulary searching (the PubMed search). So, what this article brings out, perhaps, is that full text searching brings up more relevant articles. For complete retrieval, one should use both databases, as this article concludes. One can do free text searching on PubMed so one could infer from the article that good literature searching requires the use of librarians with searching expertise, who know that good search strategies include a mix of full text searching (title searching for really high relevance) and controlled vocabulary. Previous work I have done confirmed the logical conclusion that Google Scholar favours older literature since its secret search algorithm ranks more highly linked / cited articles – see my 2005 article, which gives some comparisons of various databases/sources for various purposes, “Google Scholar: a source for clinicians?” at http://www.cmaj.ca/content/172/12/1549.full. (Have done more recent tests with similar results, although some topics now retrieve Google Book results, which confuses the situation.) In conclusion, Google Scholar may replace academic databases for some but not all purposes. For an overview on “mobile learning”, Google Scholar would provide a cross-disciplinary view pulling highly cited articles. For a thorough literature review on mobile learning, one would want articles about “students with iPhones”, which would be missed by the phrase “mobile learning” and might be covered by controlled vocabulary indexing in various academic databases. Another question is whether faculty should accept papers based on literature searches using just Google Scholar with no help from a librarian, but that is a topic for another day. Jim +++++++++++++++++++++++++++++++++++++++++ Jim Henderson Librarian (Retired), McGill University Consultant, Henderson & Associates Canadian Virtual Health Library / Bibliothèque virtuelle canadienne de la santé – Board Member (Treasurer) & CIHR Grant Co-Investigator 3546 Marlowe Avenue Montreal QC H4A 3L7 Canada E-mail: [log in to unmask] http://wikisites.mcgill.ca/globalhealthguide http://cvhl.ca http://cvhl.ca/fr