From: "Hamill, Cheryl" <[log in to unmask]> Date: Tue, 18 Sep 2012 09:53:17 +0800 Use of double quotes in PubMed turns off the automatic term mapping and is very limiting. It will ONLY search terms that are in the PubMed phrase index: http://www.nlm.nih.gov/pubs/techbull/jf11/jf11_skill_kit_pm_phrase_searching.html http://www.ncbi.nlm.nih.gov/books/NBK3827/#pubmedhelp.Searching_for_a_phra " Warning! Searching a phrase using double quotes turns off automatic mapping to MeSH terms. For example, "heart attack" will not map to the MeSH term Myocardial Infarction, whereas, heart attack will. One final note: Not all phrases are recognized in PubMed, e.g., emotionally disordered. In this case, the search results will be the same for Steps 1 and 2. Without quotes emotionally disordered is searched as: emotionally[All Fields] AND disordered[All Fields] Likewise, with quotes "emotionally disordered" is searched as: emotionally[All Fields] AND disordered[All Fields] When a quoted term is not searched as a phrase, the following message appears above the search results: Screen capture of citationcontext menu. eg Quoted phrase not found." PubMed is a wonderful database - high quality with many extremely useful features. There is no comparison between it and google scholar for most searching in medicine by experienced searchers. The data from PubMed that is used in other interfaces (eg Ovid) provide alternative interface options that all have a different range of benefits. Searchers tend to develop a preference for one or another mostly based on their in depth experience with the interface. GoogleScholar has many benefits too but as many have observed, it is a matter of the best tool for the job and for the exercise of judgement on which to use when. Clients may well find google scholar easier and quicker and many libraries have enhanced this search experience by embedding openURL resolvers into it so the discovery experience is seamless. Cheryl Hamill | Librarian in Charge Fremantle Hospital and Health Service | SMHS T Block, 2nd floor, Alma Street, Fremantle WA [log in to unmask] www.fhhs.health.wa.gov.au/library -----Original Message----- From: "Sanders, Susan U." <[log in to unmask]> Date: Sat, 15 Sep 2012 22:32:12 +0000 For clarification in speaking about searching PubMed.gov, and mapping to MeSH, try this: Use the words heart attack (without quotes). I retrieved 186,831 citations. Look in the Search Details at your query translation and you'll see the way that the PubMed system ran the search, like this: "myocardial infarction"[MeSH Terms] OR ("myocardial"[All Fields] AND "infarction"[All Fields]) OR "myocardial infarction"[All Fields] OR ("heart"[All Fields] AND "attack"[All Fields]) OR "heart attack"[All Fields] Try using the MeSH subject heading Myocardial Infarction. I retrieved 136,867 citations. PubMed uses "Automatic Term Mapping," see here for explanation: http://www.nlm.nih.gov/bsd/disted/pubmedtutorial/020_040.html If you use heart attack, PubMed "maps" the term to MeSH and also searches to retrieve phrases and individual terms that are in All Fields, hence more citations than if you used a MeSH term. What MeSH gets you is a more specific set of results. What keywords gets you (all fields) is a more sensitive retrieval, but with more irrelevant citations. Best, Susan Susan Sanders Clinical Medical Librarian University of Missouri Kansas City ________________________________________ From: Linda Schwartz <[log in to unmask]> Date: Fri, 14 Sep 2012 07:19:17 -0400 I find one point in Cynthia's posting misleading. PubMed does not convert keywords like "heart attack" to MESH headings. MESH headings are a more powerful way to search and can be searched through PubMed. Try both searches in the basic search box and you will get at least 5,000 hits difference in retrieval. (Using quotes around each phrase makes the retrieval difference even more extensive!) I think Paul's statement is spot on. GScholar content is less reliable - not unreliable but less reliable - requiring MORE analysis that I personally do not hear users doing. Also important is the algorithm upon which retrieval in Google Scholar is based rewards popularity - even if that popularity is based on a bad work that has been cited repeatedly because it is so poorly done! Educating the user is important. GScholar is just one tool in the box and you need to know how each tool works, its strengths, its weaknesses, and its coverage and apply time for analysis of results. Unfortunately, users do not educate themselves but rely on the tool to translate their words into an effective search - without bothering to find out if it really does so. Linda Matula Schwartz, MDE, AHIP Director, Library Services Lehigh Valley Health Network Allentown, PA 18105 -----Original Message----- From: Cynthia Porter <[log in to unmask]> Date: Wed, 12 Sep 2012 12:44:39 -0700 Thank you Ken, I'm glad you asked this question. I've been thinking about Google Scholar lately. I work in a medical library and I like searching in PubMed because it converts keywords to Medical Subject Headings (MeSH), so it goes beyond a keyword search (e.g., I search "heart attack" but I get all the articles with the MeSH "Myocardial infarction"). Doesn't Google Scholar depend on matching keywords? Several times I have encountered full text links to journal articles in Google Scholar for items that are not available online from our library. I think that some of these resources were posted without publisher consent. Is it wrong to refer a student to this online resource? I've sent the link to students, but not a copy of the document. This practice just doesn't feel right to me. I guess I could tell the student to search it themselves in Google Scholar, but I don't like it when people tell me to "Google it." Cynthia Cynthia Porter [log in to unmask] Distance Support Librarian A.T. Still Memorial Library, Arizona Mesa, AZ 85206