Guide
Home >> Keyword
vs. Subject Searching
The
key to being a savvy online searcher is to use common search techniques
that you can apply to any database. These will enable you to retrieve
relevant information from the thousands of records in a database.
Keyword
vs. Subject Searching:
Searching by subject headings (a.k.a. descriptors) is often the
most effective and precise way to search bibliographic databases.
However, keyword searching has its benefits too. Here are some
key points about each:
| Keywords |
vs. |
Subjects |
- natural
language words describing your topic - good to start with
|
|
- pre-defined
"controlled vocabulary" words used to describe
the content of each item (book, journal article) in a
database
|
- more
flexible to search by - can combine together in many ways
|
|
- less
flexible to search by - need to know the exact controlled
vocabulary term
|
- database
looks for keywords anywhere in the record - not necessarily
connected together
|
|
- database
looks for subjects only in the subject heading or descriptor
field, where the most relevant words appear
|
- may
yield too many or too few results
|
|
- if
too many results - also uses subheadings to focus on one
aspect of the broader subject
|
- may
yield many irrelevant results
|
|
- results
usually very relevant to the topic
|
What
are subject headings?
Subject
headings describe the content of each item in a database. You
can use these headings to find items on the same topic.
It usually is not easy to guess which subject
headings are used in a given database. Lets take an example
from the phone book's Yellow pages which also use subject headings.
If you look for the heading "Movie Theatres" you will find nothing.
Movie theatres are listed under the heading "Theatres -Movies."
How
can you find out which subject headings are used?
Knowing
the right subject headings to use will help make your searching
more precise, but how can you find the subject headings for
your particular database?
- Look
to see if your database has an online thesaurus that you can
browse to find the subject heading(s) that best match your topic.
- Some
databases also publish their thesauri in print (e.g. the Thesaurus
of Psychological Index Terms, which corresponds to the PsycInfo
database).
Another
method in finding subject headings on your topic is to:
- Start
by doing a keyword search, using words or phrases describing
your topic.
- Browse
through your results list and choose two or three relevant results.
- Notice
the Subject or Descriptor field in those
relevant records and note the terms used. Keep a list of them
to help you remember.
- Redo
your search using the subjects or descriptors you identify.
Your results will be much more precise than those from your
initial keyword search.
When
you search a database and do not get the results you expect, Ask
Us for advice.
|