Introduction to Library Research

Subject Vs. Keyword Searching

Subject Searching

When an article is indexed in a database, it is given subject headings that describe what information is covered. Subject headings are limited to a set of terms developed by the company that produces the database. To know what terms are "subject" headings, check to see if the database provide a Thesaurus or a List of Subjects.

PRO: Authors use different terms when writing about the same concept (cars, automobiles, motor vehicles, etc.). Rather than thinking of every possible synonym, find and use the subject heading for that concept to retrieve all relevant articles, regardless of the terms authors may use.

CON: There may not be a subject heading for your concept or it may be difficult to find one that exactly fits your concept.

Keyword or Phrase Searching

In a keyword search the database generates a list of articles that can have the term or phrase anywhere in the record for that article ... in the title, author, abstract or even in their subject headings.

PRO: Sometimes a concept may be a narrower aspect of a broad subject heading (text comprehension is a specific aspect of reading). Searching "text comprehension" as a keyword phrase saves you the time of wading through all the articles on "reading" that don't deal with text comprehension.

CON: Keyword searching usually retrieves a lot of articles but not all of them will use the keyword in the context you want. For example, a keyword search using "reading" might also get you articles on business management by an author named George Reading.

NOTE: When in doubt, try both kinds of searches, subject and keyword! It only takes a couple of seconds to try both to see which gathers the best results for your particular topic!

Truncation

Truncation allows you to search for a root form of a word and pick up all variations of that term. Truncating broadens your search and ensure that you retrieve all items containing some form of that word.

teen* will retrieve articles with the terms

• teen

• teens

• teenager

• teenagers

A word of warning! Truncating a word too short can retrieve too many unwanted terms.

If you want all forms of the term culture, and you type cul* your articles will contain terms that you don't want:

• cults

• cultivate

• culinary

• culminate

• culotte

• culprit

The best way to truncate culture is cultur*

Boolean Operators

The search engine of online journal indexes are based on a system of combining terms using Boolean operators (AND, OR, NOT) to control the results of your search. To use two or more Boolean operators, you need to know how to use a technique called nesting.

• Use AND to narrow a search since both terms must be present in the articles you retrieve.

children AND adolescents

The black area represents only those articles that have both children and adolescents present.

Nesting

Nesting involves using parentheses so the search engine will perform the Boolean operations in the sequence you intend. This technique allows you to build a complex search using two or more operators (AND, OR, NOT, NEAR, WITH).

risk* AND (adolescents OR teenagers )

In this search the OR operation is nested and will be performed first. Then the AND operation will be performed. The search results are represented by the yellow i.e. articles on risk taking or risky behavior and adolescents as well as items on risk taking or risky behavior and teenagers.

Field Specific Searching

Another way to refine a search is to limit your search to a field. A field is an record element containing a specific type of information about a journal article. Some examples of fields are:

• title

• author

• subject or descriptor

• journal or source

• publication date

• abstract

• full-text indicator

When to Use Field Specific Searching

1. When you want articles from a particular journal (JN psychology today.......SO journal of abnormal psychology)

2. When you want information from a specific year or range of years (PY 2000-2007)

3. When terms specified as subject headings or descriptors would be better than keywords (SU education)

4. When you want to see all the works of a particular author in the database (AU decaprio)

4. When you want to only retrieve items that appear in the title of the article ( TI text comprehension)

To find out how to do a field-specific search in a particular database, check the database's Help screens or ask a reference librarian.