Search Strategies
Background information
Secondary and tertiary sources are good places to look for background information. Background information can help you understand a topic better. While the primary literature reports on specific research, background information can give you an overview of your subject and help you identify important ideas and terminology. Good background information can also help you focus your topic, identify terms for database searching, and give you a list of articles for more information. You can find background information in encyclopedias, review articles, textbooks, and websites.
Finding scientific articles: Databases
Use search engines, such as Google Scholar, and databases to find journal articles. For multidisciplinary research topics, the Articles+ search is a great place to start. It searches many resources at once for you. When you have a discipline-specific topic, the E-Research Tools page is the best place to start. The E-Research Tools page organizes databases by subject for you. Subjects in the sciences include:
Astronomy
Biology
Chemistry
Computer science
Geology
Marine sciences
Materials science
Mathematics
Operations research
Science (general)
Statistics (academic discipline)
Finding scientific articles: Search techniques
Searching by topic
When searching for scientific literature, it is important to consider alternative words and phrases because not all authors use the same words when writing about a topic. Consider synonyms and other related terms, scientific names, and alternative spellings, abbreviations, or acronyms in your search.
Boolean operators
In databases, entering a simple phrase may not be the best way to search. Unlike search engines, many databases will treat a string of keywords as a specific phrase. To combine your keywords and phrases, you need to use what are called Boolean operators. Boolean operators are simply the words AND, OR, and NOT. They help you broaden (find more) or narrow (find fewer, more relevant) search results.
The Boolean operator AND helps combine keywords and phrases to find where the terms intersect; it narrows your search to retrieve only those articles containing all of your keywords and phrases.
The Boolean operator OR broadens your search to include documents that have any of your keywords and phrases; it will find documents that have one or more of your keywords and phrases.
The Boolean operator NOT eliminates a specific search term or group of search terms. The NOT operator is used very infrequently and should only be used when you are confident you will not eliminate articles or other information that could be useful.
Many databases guide you by including these Boolean operators in their search interface. See How Do I Find Articles? for more help with Boolean operators.
Keyword searching and subject headings
Keyword Searching is how you search when using search engines like Google. You type in words that describe your research topic and retrieve results containing those search terms. Because a keyword search looks for a match in the entire contents of a document, results will be higher in volume but may be less relevant.
In most databases, articles are assigned specific terms called subject headings (sometimes called descriptors) to describe the key themes in an article. If you locate an article or book that is relevant to your topic, you should note the subject headings that have been assigned. They can assist you in locating other relevant content. When using subject headings you search only for documents tagged with that specific subject, yielding results that will be fewer in number and more relevant.
The hardest part of doing a subject heading search is knowing what the appropriate subject heading should be. Most databases provide their own thesaurus or subject heading list to help you figure out the appropriate subject heading for your topic.
Using the thesaurus in the database SPORTDiscus, you will find that the subject heading for "knee injuries" should be "KNEE -- Wounds and Injuries."

Truncation and wildcards
Often your search words will have various forms or endings, all of which may be relevant to include in your results.
To retrieve more accurate results, most databases let you add a symbol to a word stem to pick up variant word endings or spellings. These are known as truncation and wildcard symbols. Truncation symbols allow you to search for all words that start with the same letter or letters. Wildcard symbols allow you to search for words with one or more different letters at a particular position.
The most commonly used symbols are the asterisk (*) or the question mark (?), but some resources use the number/pound sign (#), the dollar sign ($), percent symbol (%), or exclamation point (!). Unfortunately, databases do not use standardized symbols, so it is necessary to consult the online help or ask your librarian to determine what the correct symbol is.
Nesting (parentheses)
Use parentheses to specify relationships between search terms. For example, "(red OR green) AND apple" will search for "red AND apple" and "green AND apple."
Proximity operators
Use NEAR, WITH, or ADJ or ADJACENT to specify that you want to find articles with your search terms next to or near each other in the text. Check the help pages of the database you are using to see what proximity operators work for it. NEAR searches for terms near each other in the order typed or reverse order. You can specify the maximum number of words separating the search terms by adding a number after "NEAR." WITH and ADJ search for terms in the order typed; ADJ doesn't usually allow you to specify how many words separate the search terms.
