Subject Guide
PICO
PICO is a framework for asking focused clinical questions.
PICO stands for:
Patient and Problem
Intervention or exposure
Comparison or Control
Outcome
Grey Literature
You may hear your professor say that you need to look in the grey literature for information. In its most simple definition, grey literature is anything outside of the usual academic (book and journal) publishing world. Grey literature can be government documents, agency reports, white papers, and other non-published items. For example Evidence Based Clinical Guidelines could often be considered grey literature.
Evidence Based Practice Hierarchy
Hierarchy of Evidence Summary
Level I:
a. Evidence of a systematic review or meta analysis of all relevant randomized controlled trials (RCT), or evidence-based clinical practice guidelines based on the above.
b. Evidence of a systematic review of RCTs
c. Evidence of a systematic review of nonrandomized trials
Level II:
a. Evidence from at least 1 RCT.
b. Single nonrandomized trial
Level III: Evidence from a systematic review of correlational/observational studies
Level IV: Evidence from a single correlational/observational study
Level V: Evidence from systematic reviews of descriptive, qualitative or physiologic studies.
Level VI: Evidence from a single descriptive, qualitative, or physiologic study.
Level VII: Evidence of authority opinion or reports of expert committees.
Pyramid modified from: Navigating the Maze, University of Virginia, Health Sciences Library, by University of Washington. Health Sciences Library and Information Center
More information about EBP
Basic Information and Tutorials about EBP:
- Introduction to Evidence Based Medicine Tutorial - Duke University Medical Center and UNC-Chapel-Hill
Writing your topic a PIO, PICO, PICOT question:
- OHSU PICO pageThis guide leads you through the basics of formulating a PICO question.