Having a clear, manageable topic for your research is key to research success.   As you think about your topic, consider how you can specify the main concepts that are part of your topic. For example, if you are interested HIV transmission prevention programs for prisoners, you can think about the “building blocks” of your question as:

A search like this will find results about HIV prevention programs for prisoners. Doing a broad search at first and then adding more terms or using the limiters in a database to narrow your results down often makes for much less frustration.

Think About Keywords

Keep in mind that there may be more than one term that means the same thing, or something very similar.  For example:

Prisons or jails or inmates or prisoners or incarceration

teen or teenager or adolescent or youth

HIV or AIDS or STD or sexually transmitted diseases

You will also find keywords to try in your readings and in your notes from class.   Making a list of synonyms for your search terms is often a good strategy for searching, to be prepared in case you don’t get as many results as you had hoped.

Consider Descriptors (controlled vocabulary)

Many databases also use specific keywords or terms called descriptors that are assigned to articles on that topic.  Once you know the descriptors for your topic it can make it easier to pull all articles on the same topic together at the same time.  In many cases the descriptor will be the medical term – just be aware that terminology changes.   You will find descriptors (often called Subject Headings) in database search results by looking at the individual records for articles.  Many databases for the health sciences (PubMed, CINAHL) use the Medical Subject Headings (MeSH terms), so becoming familiar with the MeSH terms associated with your topic will be useful.  To locate specific MeSH terms in PubMed, use the “MeSH” dropdown option from the search box.  Click here more info about PubMed and MeSH terms.  The PubMed Tutorial from NIH is an excellent way to learn how to construct effective searches in PubMed, or look at the NIH MeSH Tutorial for a quick overview.

Here are a few examples of keywords and their MeSH terms (some terms are more obvious than others!)

Combine Terms

Once you identify the terms (keywords or descriptors) applicable to your question or topic, put them together with Boolean operators such as AND (for more precision in your search), OR (to enlarge the pool of results when more than one situation is concerned), or NOT (to exclude possible elements that might jeopardize quality for quantity in your results.  (Be careful using NOT though, as you may exclude useful results!)

For example, if you are interested in researching heroin and harm reduction methods your terms might be:

And your broad search might look like this:

Heroin AND harm reduction

Or a more complex search:

(Heroin OR injection) AND (addiction OR abuse) AND ((harm OR risk) AND reduction)

Going back to our prisons and HIV topic, a search to exclude any results about injection drug users would look like this*:

(prisoners NOT intravenous drug users) AND HIV

(*However, remember any articles that contain BOTH prisoners and intravenous drug users will be excluded from your results because we specified that we do not want the term injection drug users to appear in the results at all!)

Tip: Each database has its own thesaurus to organize articles on certain topics. Take a look at the database’s thesaurus to see if it uses a different term if your search does not yield enough results on your topic. 

Tip: Put quotes around search terms that are phrases (contain more than one word).  For example, placing quotes around “Mediterranean diet” will locate articles for you in the databases containing the phrase “Mediterranean diet” and should weed out all the articles where those words appear separately from each other (for example, an article about trying to be on a diet while on a cruise ship on the Mediterranean Sea!).