Psychology: Database Search Tips

Boolean Operators

The words AND, OR, and NOT are command words that connect keywords to achieve different results.

AND

• Results contain sources with all search terms
• Narrows the number and focus of results

OR

• Results contain sources with any of your search terms
• Broadens the number and focus of your results
• Used with synonyms or related terms

NOT

• Eliminates sources containing the term after NOT
• Narrows the number and focus of the results

AND

gender AND aggression gives you results that contain these words together in the same record

OR

gender OR aggression gives you results that contain either of the words regardless of whether they appear in the same record

NOT

gender NOT sexual identity gives you results that contain gender and no mention of sexual identity

Truncation

Truncation is a search technique that broadens your search to include various word endings. To truncate your search terms, replace the word ending with an asterisk *

Adjacency

Adjacency is a way to tell the database that you want words to appear in a specific order. Some databases will do this automatically, but some will not. Add quotation marks around the search terms to force adjacency if needed.

Subject Headings

Subject headings are database-specific structured vocabulary and preferred terms that field scholars use to discuss their topic.

• E.g., play (natural language) vs. childhood play behavior (subject heading)

Characteristics of Subject Headings (From MIT Libraries):

• Pre-defined "controlled vocabulary" words used to describe the content of each item in the database
• Less flexible to search by - need to know the exact term used
• Databases look for subjects ONLY in the subject heading filed or descriptor
• Databases look for subjects ONLY in the subject heading filed or descriptor
• Use if too many results - can help focus on one aspect of a broader topic
• Results are usually very relevant to a topic

Characteristics of Keywords Characteristics (From MIT Libraries):

• Natural language and words describing your topic
• More flexible to search with; can combine together in multiple ways (AND, OR, NOT)
• Databases look for keywords everywhere in the record
• May yield too many, too few results, or irrelevant results

When you search for articles, you can use any combination to find what you're looking for.

• keyword + keyword 
• subject heading + subject heading
• keyword + subject heading

Since subject headings are created by someone other than you, you should look for them within the results of your keyword searches or a database thesaurus. Most databases will have a thesaurus.

Subject headings are usually listed within the details of an article. You can also find a thesaurus link within PscyInfo in the Advance Search options above the advance search.

PubMed calls their subject headings MeSH Headings.

An example of when a subject heading might be useful is when you search for aggression. This includes thousands of records, some of which you may not be interested in.  You may find it useful to look at the Thesaurus for a more precise term, like relational aggression.

Limiters/Filters

Limits provide database-specific recommendations for narrowing a search. Applying limits will filter out results that don’t meet your search requirements. 

Be careful applying the date limiter. It can be too limiting, and you may miss foundational articles that support your topic. Using the Times Cited function can be a better way of finding more recent articles.

Examples of limits/filters:

• peer review
• study type
• format (review, article, book chapter)

Abstract

The abstract of an article is a brief summary of the article's contents that can help you determine if you want to read the full text. The abstract is usually listed within the search results under an article title.  You can use the abstract to help modify your search by skimming it for additional keywords.

Bibliography

Scholarly articles often have extensive reference lists or bibliographies. Some databases include these in the record, which you can link directly to. You can use references in a bibliography to learn about the research used in writing the article, which may lead you to additional articles about your topic.

Times Cited/Cited By

Think of Times Cited references as the opposite of a bibliography. Where bibliographies include references older than the article, Times Cited references are newer than the article. It means someone found the information in the article valuable and cited the article within their own writing.

Times Cited references can help you find more recent articles than the one you are reading.

Related/Similar Articles

When you find an article that you think will be good to use, you can take advantage of “related articles” to find similar articles.  There are different formulas for determining how an article is “related,” but it usually combines the same keywords and subject headings.