1. Use Dropdown Menus in Advanced Search Screens

The default search for most databases and catalogs is a keyword search. If you make no changes, you'll be doing a keyword search when you enter a term into these boxes:

EBSCO EBSCO Discovery Service Basic Search Box

Library Catalog (Primo) basic search box

Use the Advanced Search links in these interfaces to switch to a screen where you can specify that you'd like to do subject heading search.

EBSCO Discovery Service Advanced Search Screen

Library Catalog (Primo) Advanced Search Screen

2. Click a Hyperlinked Subject from a Relevant Record

If you see a record in a database search result that looks useful to you, click its title to see the details about the item. In most databases, there will be section of the record containing the subject headings assigned to it. They are hyperlinked. Click any one to perform a new search for that subject. 

Note that you can only search one heading at a time using this method. You'll probably find it useful to keep a list of the helpful headings you find as you go so you can track of them and try different combinations of subject headings. Use the Advanced Search screen to create new searches with several different subject headings, or with a combination of subject headings and keywords (or subject headings and authors).

Detail Screen of a Sample Record from EDS (ebook)

1. Be aware of database variation

Subjects are in a field simply called Subject in the CTU catalog (Primo), but in databases, the field may have a different name:

Subject headings

Subject terms

Descriptors

Different databases also use their own controlled vocabularies. When switching from one to another, you may need to spend time determining what term that particular databases uses for your topic. 

Also remember that EBSCO Discovery Service is a tool that searches many databaes at once. If you use the Advanced Search in EDS and search by Subject Term, you may notice records from only a few databases in your results. That often means that the other databases within EDS use different terms than what you've enetered for your subject search.

2. Use the Cataloging Information from Books

Books printed in the United States are catalogued using subject headings established by the Library of Congress. Almost all books in the Bechtold Library will have these headings printed on the left side of one of the first few pages of the book. If you can find one book that fits your topic well, search for its subject headings in the library catalog or in databases like Atla Serials Plus (which uses headings that are very similar to Library of Congress headings).

The section is often identified as "Library of Congress Cataloging-in-publication Data". The subjects headings will be numbered:

To search for other books on subject #1 in a database, type it just as it appears in the book (on a keyboard, type two hyphens in a row to get the long dash that appears between the terms Feminism--Religious Aspects--Christianity)\

3. If your research is in a new area of study....

Language changes quickly, especially in areas related to science, technology, and culture. It takes time for the groups that establish headings to decide on the terms they'll use to describe emerging concepts. if the subject you're researching involves terms that haven't been used in professional literature very long, there may not be a subject heading for it yet. In those cases, your research will have to rely on keywords.

While databases cannot understand natural language, database searches can be made very precise using Boolean operators. Boolean operators tell databases exactly how you want your search terms combined for the optimal results.

There are five Boolean operators and all library databases understand them.

The chart below briefly describes their functions.

More Details

"Quotation Marks"

Quotation marks tell the database to take the phrase as a whole, and search for the words together, and in order. 

Example: Searching wild geese:

• Without quotation marks, the database finds the word wild and the word geese separately. You might get search results about how well domestic geese survive in the wild.
• With quotation marks, the database ignores articles that do not contain the exact phrase "wild geese". It won't bring up "geese wild," or "wild animals, such as Canadian geese."

Truncat*

The asterisk (*) is a kind of wild card that tells the database to find multiple "endings" of a word.

Example: Searching feminism.

• • Without truncation, you get only feminism, but not feminist.
  • When you truncate as feminis*, you get both feminism and feminist.

Be careful of truncating too early in the word itself.

• If you truncate as femini*, you will get feminism, feminist, and also feminine, which may not be on topic.

AND

AND joins two or more concepts by telling the database that both/all of these keywords must appear in the search results.

Example: Searching for Plato's idea of the good life.

• Without AND, most databases assume you meant AND anyway; however, some databases may return items that mention Plato, or the "good life," but not both.
• With AND, the database knows that you need articles that contain the word Plato and the phrase "good life." 

Hint: if your topic is "the X of Y" or "the impact of X on Y," or "X as a Y," or "X in Y," you need to use an AND to join concept X and concept Y.

OR

OR joins two or more keywords for the same concept by telling the database that one or more of them must appear in the search results. It is useful when:

• You have multiple ways of saying the same thing, such as U.S., U.S.A., America, and United States.
• You are searching for two things having to do with the same concept, such as vaccine AND (measles OR "chicken pox")

Example: Searching for rabies in mammals

• Without OR, you could search rabies bats possums "feral cats" and the database would return results that had all of those keywords. You would miss out on the results that talked about rabies in only one of those kinds of animals.
• With OR, you search rabies AND (bats OR possums OR "feral cats") and the database knows that you need to know about rabies in bats, or rabies in possums, or rabies in feral cats, or any combination of the above.

Hint: always put parentheses around groups of keywords joined by OR.

(Parentheses)

Parentheses tell the database that it cannot just work from left to right - it has to perform certain operations first. That is why you need to put parentheses around groups of keywords joined by OR. 

Example: Searching the use of bats and frogs for mosquito control

• If you search "mosquito control" AND bats OR frogs, the database works left to right. First it looks up "mosquito control" AND bats and then it looks for frogs, so you get search results that are about frogs but have nothing to do with mosquito control
• If you search "mosquito control" AND (bats OR frogs), the database knows that it needs to look up bats OR frogs first. Then it looks in those results to find "mosquito control." 

You can also nest parentheses (put one set inside of another) and the the database will work from inside out.

• (((bats OR frogs) AND "mosquito control") AND (playground OR "golf course")): First the database searches bats OR frogs. It searches inside those results for "mosquito control." Then it searches inside those for results that mention either playground or "golf course" or both.

NOT

NOT excludes search results that contain the keyword(s) following it. 

Example: Searching for impact of smog on asthma, but you do not want to read about China.

• Search (smog AND asthma) NOT China, and the database first looks up articles that contain both smog and asthma, and then eliminates all the search results that contain China.

When you might need to use NOT:

• When you are only interested in part of a topic, like dogs NOT poodles. 
• If there is a certain word/phrase associated with your topic that implies a biased point of view, like immigration NOT "illegal aliens"
• If the word/phrase you want to use is most often used as part of a phrase that has to do with something off topic, likeclimate NOT "climate change"
• If a word/phrase for your topic is also used to mean something else, like archive NOT (email OR database)

It is feasible that you may have such a complex search to perform that you might require the use of all six of the Boolean operators to get optimal search results.

For example, let us say that you are looking for medicines or other medical interventions for seizure disorders other than epilepsy.

This search, using all of the Boolean operators, might look like this:

medic* AND (seizures OR "seizure disorders" OR "convulsive disorders" OR convulsions) NOT epilepsy

The Atla Thesaurus

Databases produced by Atla include a valuable tool to help you understand the subjects headings they use and how they're related to each other: the Thesaurus. It's particularly helpful when you're searching by subject and getting no results for a topic you expect to find articles on. It's likely that you're using a subject term that isn't used in this database. The Thesaurus helps you find the right term for your topic.

Access it by clicking the Thesaurus link at the top of the database inteface:

Enter your search term in the second box on the page. For your initial search, leave the button below the search box set to find headings that begin with your term. 

In this example, I'm looking for articles on the sacrament of reconciliation, but have found only articles on the concept of reconcilation in general, so I've gone to the thesaurus to search for the term.

The thesaurus search results show me that the term for my subject in this database is Confession--Catholic Church

While using the Thesaurus tool, I can click on the heading Confession--Catholic Church to learn details about  it and see related terms:

This tells me that I could search for the subject Sacraments--Catholic Church to see articles that are broader (but may be relevant to my research) or search for Confession (Canon Law) if I'm interested in that narrower aspect of my topic.

The two terms that appear next to "Used For" are not subject headings used in this database. I should not use Reconciliation (Sacrament) or Penance (Sacrament) as a term in subject searches! Even if the published articles use those terms, the articles will be categorized under the subject heading Confession--Catholic Church in Atla databases.