It is important to make general ideas and topics into concise questions before you begin your search. This helps keep you focused on your precise topic when searching. Your question should have between two and four main concepts; with any more than that you should consider creating two or more questions. The PICO, SPIDER, SPICE, and ECLIPSE tools (see table below) make it easy to identify the concepts in your search.
Is kineso tape more effective than ibuprofen in relieving back pain during athletic events?
Are surveys effective in finding out if wheelchair users are satisfied with classes on how to use a wheelchair in winter conditions?
Do people, in an outpatient setting, who take classes on how to lower cholesterol see their cholesterol level go down more than those who do not take the class?
Are allied health students who receive test and essay scores within 14 days of submission more confident of their progress in their education?
Databases use rules known as Boolean operators to build a search. These allow you to combine concepts in different ways.
When searching you sometimes need to think of synonyms for a concept in order to capture all the information on that concept. For example, to capture all the information on heart attacks you would search heart attack  OR myocardial infarction  OR cardiac arrest 
Do not overdo it when it comes to synonyms: only use the most logical and do not include broader concept terms.
AND is used when you want the results to contain all of the concepts important to your research. For example, to capture information on the use of exercise by an elderly population as part of a fall prevention program, you could search exercise AND elderly AND fall prevention
Be careful of having too many concepts, because you may end up with zero results.
NOT tells the database to ignore concepts that may be implied from your search terms. For example, if you were searching for articles on nursing and education but you did not want articles on breastfeeding, you might search (nursing  AND "education classes ") NOT "breastfeeding "
Be careful about using NOT as you may inadvertently exclude helpful articles from your search that just happen to mention a term.
|Concept 1||Concept 2||Concept 3|
terms and phrases that reflect concept 1
terms and phrases that reflect concept 2
terms and phrases that reflect concept 3
Example: Is constraint induced movement therapy effective for stroke patients?
|Concept 1||Boolean||Concept 2|
cerebral vascular accident
constraint induced movement therapy
Using parentheses the search would look like this:
(stroke OR cerebrovascular accident OR cerebral vascular accident OR CVA) AND (constraint induced movement therapy OR CIMT)
Records in library databases have fields containing specific pieces of bibliographic information.
Example of a CINAHL record with common fields highlighted
Limiting your search to specific fields in a database can yield more precise results:
Look for the Advanced Search page to search specific fields in a database.
Subject headings are specific terms or phrases that describe the content of each item in a database, while keyword searching is how you typically search web search engines. Searching by subject headings (such as MeSH) is the most precise way to search article databases. It is not easy to guess which subject headings are used in a given database. You might have to find what term is used for a subject first before using it: for example do you use "Stroke" or "Cerebrovascular Accident?"
Here are some key points about each type of search:
To find subject headings for your topic:
Another way to find subject headings:
Many databases allow you to specify that the words you are searching are within a certain proximity of each other. Because of their proximity the two words can have a relationship. Proximity operators are more specific than Boolean operators and make your search more precise. Proximity operators also vary by database, but some common ones include: W# (With, Within) and N# (Near)
Proximity operators vary from database to database (ADJ#, W/#, N/#, NEAR#, etc); you need to check the Help section of each database to see what they use.
Warning: when using truncation make sure to use enough of the root word to express your idea; use too little and you will get bad results.
Search interfaces differ from database to database, so it's often helpful to look at the help documentation for the specific database you're interested in using. Here are some helpful guides by database: