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Evidence - Based Practice

This guide is a collection of resources for learning Evidence-based Nursing.

Database Search Strategies

Anatomy of a good clinical question: PICO

PICO is a mnemonic that helps one remember the key components of a well focused question. The question needs to identify the key problem of the patient, what treatment you are considering for the patient, what alternative treatment is being considered (if any) and what is the outcome you want to avoid or promote. 

P = Patient or problem

How would you describe a group of patients similar to yours? What are the most important characteristics of the patient? This may include the primary problem, disease, or co-existing conditions. Sometimes the sex, age or race of a patient might be relevant to the diagnosis or treatment of a disease.

I = Intervention, prognostic factor, or exposure

Which main intervention, prognostic factor, or exposure are you considering? What do you want to do for the patient? Prescribe a drug? Order a test? Order surgery? What factor may influence the prognosis of the patient? Age? Co-existing problems? Has the patient been exposed to something? Asbestos? Cigarette smoke?

C = Comparison

What is the main alternative to compare with the intervention? Are you trying to decide between two drugs, a drug and no medication or placebo, or two diagnostic tests? Your clinical question does not always need a specific comparison.

O = Outcomes

What can you hope to accomplish, measure, improve or affect? What are you trying to do for the patient? Relieve or eliminate the symptoms? Reduce the number of adverse events? Improve function or test scores?

This step requires you to combine alternative words and components using Boolean operators and other search techniques.
Tip: When using Boolean operators, remember to combine all the synonymous/alternative words that represent one component with OR. Combine the sets of different component with AND and use NOT sparingly.
Tip: Avoid searching for outcomes since the words used to describe outcomes can be very complex and not well indexed in databases.

Finding evidence involves searching health databases. As no one database contains all the available health literature, it is important to widen your search.The following databases contain systematic reviews and meta-analyses of healthcare interventions, diagnostic tools, and more.