General knowledge about a condition, test, treatment, population, etc.. that can be answered by background sources like handbooks, textbooks, or other references materials. Example: “What are some symptoms of Mediterranean Fever?
Specific knowledge to help with clinical decisions or treatments, and can be found in various resources (articles, dissertations, systematic reviews, meta-analysis, best practice guidelines, and more).
Formulate your foreground research question using the PICO model. Additional variations also exist: PICOT, PICOS, PICOTS, PICOTTS.
P: Population (Patient or Problem)
I: Intervention
C: Comparison
O: Outcome
T: Timeframe / Type of Question (Systematic review/RCT...) / Type of Study (Therapy/Diagnosis/Prevention) (Optional)
S: Setting (Optional)
For examples of focused questions and more details about PICO, check out this guide from University of North Carolina and the tutorial from Binghampton University Libraries.
Before starting your search, it's important to be familiar with the rank of information in order to find the best evidence available. The video below by Anatomy Plus provides a clear explanation of the levels of evidence in different sources of health information.
Following up on the Evidence Hierarchy, what are the filtered and unfiltered information sources and where can you search for them? Check out the next tab.
Also called secondary or pre-appraised information, it consists of primary literature (original, unfiltered data or reports) that has been reviewed, sometimes over a long period of time, for accuracy and looks at how to apply it to practice.
Some databases to locate filtered information:
This is the raw, original data or reports. It has not been reviewed as extensively as filtered information and may still have some flaws or bias. They are also much more difficult to interpret and apply to practice because of the lack of review.
Some databases to locate unfiltered information:
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