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Phoenix Residents and Fellows

Guide for Creighton University Arizona Health Education Alliance Residents and Fellows

Using Boolean Operators

Venn diagram with the overlapping section shaded to show the boolean AND The AND operator narrows a search, retrieving only records containing both term(s). AND is used to narrow a topic to a specific aspect.

Example: anorexia AND "college students"
Venn diagram with all sections shaded to show the boolean OR The OR operator broadens a search, retrieving records that contain either term, but not necessarily both. It is used to combine synonyms or related concepts.

Example: anorexia OR bulimia
Venn diagram with only one section shaded to show the boolean NOT The NOT operator also narrows a search by removing all records that contain a particular word or phrase.

Example: anorexia NOT bulimia

The NOT operator is rarely used. It often screens out useful records.

Key Search Techniques

Quotation Marks

Using quotation marks in a search tells the database that you are looking for an exact phrase. Because of this, you only need to use quotation marks for a concept that is two or more words. For example if you were researching Social Security, using quotation marks ["social security"] would tell the database that you only want search results where Social Security appears as a phrase.

Without the quotation marks, the database actually reads your search as [social AND security]. This is an important concept to remember. Library databases will interpret strings of terms without any quotation marks or Boolean operators as being connected by the term AND. For example a search for [climate change glaciers] is translated by the database as [climate AND change AND glaciers]. This could return search results that are unrelated to your information need.

Truncation and Wild Cards

Truncation refers to shortening a word or eliminating characters in order to pick up variant terms in a database. Symbols are used for truncation. The most common symbols are the asterisk (*), the question mark (?), the pound sign (#), or a dollar sign ($). These symbols vary from database to database but are often indicated on a database's "Help" page. Examples of truncation:

  • child* - includes child and children
  • disab* - includes disabled, disability, disabilities
  • environment* - includes environment, environments, environmental, environmentalist, etc.

Wildcards are used for internal truncation. This will replace a single character in a search term. This is useful if a word has a letter difference between American English and British English or if a word is irregularly pluralized. The symbols used are different from regular truncation, but can be determined on a database's "Help" page. Examples of using the wildcard:

  • wom?n - includes woman and women
  • colo?r - includes color and colour