Researching and Writing a Paper: Limiters

Limiters:
Limiters let you focus your search so that the information retrieved from the databases you search is (probably) closer to what you are looking for. Limiters vary among databases so you should spend a few minutes exploring the search pages of the database you're using to find the available limiters.
Some common limiters that might appear below the Search Options tab, or on the left of a results page, include:

• Full-text – Click to limit results to articles with full-text (more about full-text).
• Peer Reviewed – Limits search results to articles from peer-reviewed or refereed journals (this should almost always be selected, and some databases contain only peer-reviewed articles).
• Journal/Magazine – Enter a journal/magazine name in this field to limit results to articles only from that title (sometimes available as a drop-down box).
• Date Published – Use this option to search for articles within a specified date range.

You can usually use as many limiters as are available.

Introduction to advanced search limiters:
Many databases have several more ways to limit or refine your search results. Look for the Advanced Search link to see these additional options. In some databases they may also appear on the search results page. Some examples of further ways to limit your results might be:

• Language - (the language the article is in)
• Publication - (select one or more journal names)
• Source type - (such as Books, Conference Papers & Proceedings, Audio, Video, Blogs, Podcasts, Dissertations/Theses, Magazine, and Newspapers)
• Document type - (such as Advertisement, Annual Report, Article, Audio/Video Clip, Back Matter, Bibliography, and Biography)
• Subject - (a variety of controlled subject terms assigned by the author or publication)

Some of the other limiters sometimes include:

• Company Name
• North American Industry Classification System (NAICS) code
• Population group
• Age group
• Educational level
• Clinical query
• Population group
• Animal trial/study
• Conference (IT research is often published in conference proceedings, as they come out more rapidly than peer-reviewed journals)

Any time that you want to use a limiter that does not seem to be available try using that word (Company Name, NAICS, Publication, Document Type, and so on) as a Keyword.

Common advanced database limiters:
ProQuest databases have additional ways to limit results by source and/or document type. Many databases have similar features. Below the search boxes there is the Source type box for selecting different types of sources, and the Document type box for selecting document types such as Annual Report, Case Study, Editorial, Illustration, and so on. (Note: the boxes have lots of options in them.)