Library Tutorial - Searching Electronic Databases - Subject Searching

Trying to find all the variations and synonyms for your keywords can be frustrating and time consuming.  Many databases offer an alternative known as subject searching.  Each record in the database is assigned a subject heading from a predetermined list of possibilities, sometimes known as a thesaurus or controlled vocabulary.  This list ensures that no matter what terminology the author used, articles on the same topic can be retrieved with one subject heading.

• Canine vs. feline:  who is the smartest?
• Cat and dog IQ's.
• Rover's brain:  better than we thought.
• Cats and dogs battle on the intelligence front

What do these articles have in common?  Remember, databases are about matching searches to words in the article record.  These articles use many different keywords:  canine, feline, smartest, cat, cats, dog, dogs, IQ, intelligence, brain.  But even though they use different terminology, they are all on the same topic.  Let's look at the records of the first three articles:

Notice how the records differ in title, author and journal names, but share some of the same subject headings?  By doing subject searches for dogs, cats, and intelligence, we could gather articles that share the same topic but have varying wording.

Finding Subject Headings

Some databases will suggest possible subject heading when you do a keyword search.  For example, if you type bedsore into the nursing database CINAHL, the database suggests the subject heading pressure ulcer.

For other databases, do a keyword search and look at the record of a relevant article on your topic.  If you look in the subject headings area (sometimes called the descriptors), you will find relevant subject headings.

Different databases use different subject headings.  For example, one database may use Learning Ability instead of Intelligence.  When you are searching a wide variety of databases, be prepared to deal with many different subject headings.

Sometimes a topic may not be popular enough or is too new to be given its own subject heading.  In cases where there is not a lot written on a topic or you are having difficulty finding a suitable subject heading, you should return to keyword searching.  Don't be afraid to try both types of searching.

next - Keyword vs. Subject Searching