PubMed is a database which is maintained by the National Library of Medicine and is available to the public at no charge. This database is available online at http://www.ncbi.nlm.nih.gov/PubMed. The information indexed by PubMed includes Medline, OldMedline (articles from the 1950s to the mid- 1960s), as well as citations for additional life science journals.
This database is especially helpful when looking for off-label uses of medications. For example, if a prescriber contacts you asking for information about the efficacy of fluoxetine in treatment of anorexia nervosa, it may be appropriate to seek information from the primary literature. A PubMed search might be a good place to start this search. When performing a search using PubMed one can begin with just a key word, for example, fluoxetine. As Figure 1 shows, just using the term fluoxetine yields in 10,310 results. The results can be narrowed by entering a second key word, such as anorexia nervosa, and combining the two terms with the Boolean operator AND.
While the addition of a second search term (see Figure 2) did narrow the results, there are still 88 results that match these two terms. At this time it may be wise to explore the limit options provided by the database. Limits allow the user to restrict the number of results returned for a search. Some databases allow searches to be limited by a variety of factors, including language of publication, year of publication, type of article (e.g., human study, review, case report), or type of journal where publication is found. Since the requestor is seeking efficacy data, it is appropriate to limit these search results to just clinical trials.
Multiple key word search.
By limiting the results to only human clinical trials published in English, 23 citations of possible interest have been identified (Figure 3). It is now necessary to look at the abstracts for these citations (Figure 4) and determine if these are helpful to provide a response to the query. By clicking on the blue hyperlink an abstract is displayed; this abstract summarizes the information in the article, as well as provides complete citation information for that specific article. If the publisher’s Web site offers full text of an article, a link is provided at the top of the page to the journal Web site. Some journals charge a fee for access to the full-text article while others do not. Those journals not charging for an article are clearly marked as “free full text.” You can then select that icon and go directly to a full-text PDF or html of the desired article.
Results of search with restrictions.