Public Health

How do you find the most relevant/recent research on your topic and be reasonably confident you haven’t missed any important studies? You need to create a search strategy, a systematic way of locating relevant materials on your topic.

The steps below yield a big payoff in terms of searching efficiently and effectively.

1. Focus your topic: Choose something that interests you! Then identify the question you're trying to answer. For example: Do flu shots cause complications in pregnant women?

2. Select keywords and concepts for your topic. List only terms that are crucial to your topic (primarily nouns) and their synonyms: flu shots, influenza vaccines, pregnant women, pregnancy, fetus, complications, issues, pregnancy outcome, etc.

3. Choose appropriate databases:  review the descriptions on the database list. Check for subject headings (more about this later on this page).  For example, the best terms found in the MeSH database (in PubMed) for our topic are influenza vaccines and pregnancy complications.

4. Write a search statement (This is what you would type in a database search box): influenza vaccines AND pregnancy complications.  Usually search terms are nouns.  Use AND (in all caps) to combine search terms. This way, the database will only retrieve results that contain both terms.

5. Run your search and evaluate the results.  Keep you searches broad when you first start searching. 

6. Revise as necessary. If you have too many hits, set (additional) filters/limits; for too few hits use additional synonyms or broader search terms.

Watch this video on how to construct sophisticated database search queries using Boolean operators.

(Source: Lister Hill Library of the Health Sciences, University of AL at Birmingham)

It's tempting to enter search terms into the box without giving them any thought. After all, you can Google almost any topic and get some results.

• But are the results credible?
• Are they relevant?
• How do you know whether you missed an important study?

This is where databases and subject headings come in. Research is most readily accessible in databases, and using subject headings can lead to more relevant results. Most databases have a tool for finding subject headings (e.g. CINAHL Headings, MeSH in PubMed, etc.)

Subject Headings: Standardized search terms that are assigned to articles based on their content; subject headings help to pull all information on a particular topic together, regardless of spelling variations and/or differences in what specific topics are called. Subject headings help you focus your searches.

Keywords: You can only search Google with your "best guess" keywords because it's not organized like databases; all of the hits you retrieve contain your term, without regard to overall content or context. This is why you get so many irrelevant results.

Watch this video to learn about the difference between subject headings and keywords, and how this affects your search results. (Created by the Wellington Medical and Health Sciences Library, 2010.)