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NS 400: Nursing Research

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Use PICOS to develop a clear idea what information you are seeking.

PICOS was developed by faculty at McMaster University.

P Population/Patient/Problem For which group do you need information?
I Intervention What medical event do you need to study the effect of?
C Comparison What is the evidence that the intervention produces different results than a different or no intervention?
O Outcome What is the effect of the intervention?
S Setting/Study Type

Where is the research done (e.g., ambulatory setting) or type of study (e.g., RCT)?






Levels of Evidence

Level 1     Systematic reviews or meta-analyses
Level 2     Randomized controlled trials
Level 3     a. Cohort studies (with control group)
                  b. Case-controlled 
                  c. Observational studies (without control group)
Level 4     Expert opinion, physiology bench research, or consensus

More at Centre for Evidence-Based Medicine

Dr Joseph F Smith Medical Library, Aspirus