A PGI LIBRARY TUTORIAL

Transcription

1 A PGI LIBRARY TUTORIAL EBSCOHOST DATABASES Part II II. ADVANCED SEARCH TECHNIQUES There are a number of ways to refine your search with the intention of increasing your results and/or making them more relevant or meaningful. Here are a few useful methods: You can use the special refine tools available for cross-database searching and for each individual database. You can add synonyms and related terms by using Boolean operators (AND, OR, NOT). You can search specific fields within a record. You can use search phrases or word-adjacency techniques. Refine tools Limit your results When you begin your search in EBSCOhost, you will see limiters available for all databases ( Limit your results ). Two of the most useful are Linked to Full Text and Peer Reviewed. If you click inside these two boxes, you will retrieve only full-text scholarly articles (i.e., only those which appear in academic journals). (As you recall, you can also limit your results to full-text and/or peer-reviewed articles after you run your search, using the Limit your Results panel on the right-hand side of the screen.) NOTE: As mentioned earlier, be aware that the library also subscribes to many print journals, so that those articles only available in abstract form in EBSCOhost may still be available to you in print (hardcopy) from the library. If the library owns the journal, you will see that information indicated below the citation. 1

2 View of the Limit your results options Special limiters In addition to the limiters mentioned above, you can further fine-tune your search by using limiters available for each individual database. For example, you will see that the APA databases (in this example, PsycINFO) will allow you to limit your results by Publication Year, Age Group, Methodology, Document Type, and other parameters. 2

3 To use these special limiters, simply enter your keywords in the search box, select your limiters from each database s listing, and click the search button. Boolean operators Up until now, we have been combining search terms using the keyword search mode. Another search mode available to you in EBSCOhost is Boolean searching, which makes use of the operators AND, OR, and NOT to combine terms. Boolean operators allow you to specify how you want EBSCOhost to perform your search. The AND command requires that all words be found within the same article; for example: grief AND adolescent requires that BOTH words be present in a single article. (As in Google, the EBSCOhost database defaults to an AND search when words are separated by spaces only.) Using the AND command between words will decrease your results since you are asking for all words to be present in an article. The OR command allows you to include synonyms and related words. By using the OR command, you are asking that either one word or the other be present in a single article; for example: grief OR bereavement will find those articles that mention either grief or bereavement but not necessarily the two words together within one article. Using the OR command will increase your results since you are asking for either word to be present in an article. 3

4 The NOT command excludes words. For example, death NOT suicide will exclude all articles that mention the word suicide, even those that also mention the word death in combination with suicide. It is a very powerful command that may exclude potentially useful articles; for this reason, use this technique only in rare situations or maybe not at all! Performing a Boolean search To use Boolean operators, you will need to Type in your search strategy, using a separate box for each concept level [item 1 below]. We will use the following terms: AND AND AND adolescen* OR teen* grief OR bereave* OR mourn* death OR loss parent* OR mother* OR father* Add another search row by clicking on Add row next to the last search box (as necessary) [item 2]. Click on the bubble (radio button) labeled Boolean/Phrase under Search options [item 3 below]. Note: EBSCOhost will automatically perform a Boolean search, however, when you use Boolean operators in the search boxes, even if you leave the radio button highlighted on Find all my search terms. Keep the default to AND between each box (since we are combining separate concepts) Select search limiters, if desired; in the sample, we will limit our search to peerreviewed only (which, as mentioned earlier, instructors prefer) [item 4 below]. NOTE: It is a search convention to capitalize Boolean operators so as to distinguish them from search terms, although it is not absolutely necessary to do so. Also, in a typical search situation, you will want to try various combinations of terms to see which yield the best results. View of a Boolean search 4

5 After entering your search, click the search button. Below is the screen showing our search results. 5

6 By using the OR command to include synonyms and by placing these synonyms in the same box, we have increased our article results from the original 146 peer-reviewed articles found earlier to 380. It is always important to review your results, however, to ensure that you are retrieving relevant articles. If you are not, there are other search techniques to use, which are described below. Field searching Sometimes you will find that your search has retrieved too many irrelevant articles. To make your search more precise, you may want to search within a specific field. If you click on the drop-down menu, you will see specific fields within a record that you can search. View of screen showing results of subject-field selections One of the most useful fields to search is the subject field. For example, in our sample search, we may want to find only those articles that mention (grief OR bereave* OR mourn*) and (death OR loss) in the subject field. (Again, subject headings are assigned by database indexers and sometimes article authors. We can cover related subject headings in this way.) To do this, use the drop-down menu to change the search mode for these concept levels from Select a Field (optional) to SU Subject Terms. 6

7 You will see that we have retrieved 182 peer-review articles, each of which will pertain to the subject areas we selected. Proximity searching Sometimes you may want to employ the technique known as adjacency or proximity searching. For example, if you d like to find articles that include such phrases as parental death, parent s death, death of a parent or death of both parents, you can tell EBSCOhost to search for one term within a certain number of words from another. One type of proximity search is the NEAR (N) command. For example, parent* N5 death will find parent* within five words of death, in either order. 7

8 Below you will see how the two words appear in relation to one another in a record. Another proximity operator is W (within), which will find two words within a specified number of words near each other, in the order that you enter them. For 8

9 example, parent* W10 death will find parent* within ten words of death, strictly in that order. Searching a single database Up until now, we have been searching several databases at once. You will often find that single-database searching gives you more options than cross-database searching in regard to fine-tuning your search. A good database to search by itself because of its unique features and powerful search options is PsycINFO. And because it is the largest database by far in terms of the number of articles, dissertations, book chapters, etc. that it indexes, it will give you an excellent indication as to the variety of material available on any single topic. Choosing a new database To select a new database to search, click on the Choose Databases link: On the next screen, to select PsycINFO, click on the box next to PsycINFO (and deselect the databases you no longer wish to search) and click OK. 9

10 Searchable Fields A major difference between cross-database searching and single-database searching is that the latter will have more searchable fields in the drop down menu. Searching PsycdINFO s thesaurus (list of subject headings) 10

11 Another advantage is that you can more easily search specialized indexes when focusing your search inside a single database. (It is also possible, though more problematic, to conduct individual index searches when doing cross-database searching.) For example, in PsycINFO, you can search a detailed thesaurus of subject terms. To do so, first click on the link titled Thesaurus, located near the top of the screen. You will now be taken to a searchable and browseable index of standardized subject headings. To browse the index alphabetically, leave the radio button selection at term begins with. 11

12 View of PsychINFO s thesaurus page Returning to our sample topic, we can type in the word parent inside the browsing box (not the searching box) in order to look inside the index starting with that word. Then we click browse. The next screen will display all terms beginning with the word parent. 12

13 If you scroll down in the window you will find an official subject heading that describes well one aspect of our search topic: parental death. If you would like to conduct a search using this standardized subject heading, click on Add and you will see the term automatically entered (along with a special search prefix) inside the search box. 13

14 To add another subject term from the thesaurus, you need to browse again. For example, if you type in grief, you will be taken to the following selection screen: To add the term grief to your search box, click on the box next to the word in the listing of subject headings. Next, change the option for Select term, then add to search using to and. Last, click the Add button. (Note: changing to an AND search will cause the system to find both subject headings within the same document.) 14

15 In the next screen, you will see the term added to the search box. Now, we are able to click the search button in order to run this search in PsycINFO. The resulting set contains a total of 140 records, which are highly relevant due to the fact that you are searching standardized subject headings (also called descriptors, which is what the DE represents in PsycINFO s search language). 15

16 Explode and Major Concept searches When performing a thesaurus search, you can also specify if you d like your subject terms to be exploded or indexed as major concept headings. If you click on the box for Explode, you will search all narrower topics indexed under the term on display. For example, if you click on the box next to the heading Death and Dying (see below), you will also search for the narrower topics, Euthanasia and Parental Death. 16

17 Similarly, when you select a subject term and click on the box Major Concept, you will retrieve records for articles that treat the subject as the main emphasis of the article. Using special limiters in PsycINFO As mentioned earlier in Part I of tutorial, special limiters can help you refine a search. And in PsychINFO, special limiters can be especially powerful. For example, using our earlier subject search (parental death AND grief), we can restrict our findings to the adolescent age group (an important aspect of our original sample topic.) Note: If you wish to retrieve only peer-reviewed articles (and not dissertations or book chapters as well), you must first click on the Peer-Reviewed only box before selecting special limiters. Restricting to peer-reviewed articles. Next, to restrict this set to a particular age group, scroll down the page and click on the Age link from the panel to the left. 17

18 Restricting to an age group The next screen will display the different age groups. Click on Adolescence (13-17 yrs) to select that group. Once you click on the option, Adolescence (13-17 yrs), you will retrieve a total of 33 highly focused articles containing the parameters you ve selected. 18

19 General search tips Try both cross-database searching and single-database searching. Crossdatabase searching will yield greater results, but you may be surprised by what you find when you focus on a single database and tailor your search strategy to its features. Try both keyword searching and subject searching. Use full-text searching when you do not find information using keyword searching and subject searching; full-text searching is especially recommended for new or little-known topics. Look closely at relevant articles to find search terms and phrases you haven t already tried. When searching using Boolean techniques, enter synonyms (related concepts) in the same search box; for example, treatment OR intervention. Limit your results to Peer-reviewed articles if you need only scholarly journal articles. PLEASE GO TO PART 3 OF TUTORIAL 19