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Evidence Based Practice (EBP)

What is Evidence Based Practice (EBP)

A problem-solving approach to clinical practice that integrates the conscientious use of the best available research evidence, clinical expertise, and patient preferences and values. The University of Minnesota has developed a web page that provides definitions for commonly used terms in EBP.


The 5 Steps in the EBP Process:

  1. Ask the clinical question.
  2. Collect the most relevant and best evidence.
  3. Critically appraise and synthesize the evidence.
  4. Integrate all evidence with personal clinical expertise, as well as patient preferences and values, and make a practice decision or change.
  5. Evaluate the practice decison or change.

Well-Built Clinical Queries

"Background" Questions
Depending on your experience, you may first need to ask background questions to acquire general knowledge about a condition or thing. These commonly take the form of a question: who, what, where, when, how, why and a verb. Example: What causes SARS?

"Foreground" Questions use PICOS to seek specific knowledge (causal or predictive) to assist in clinical decisions or actions.


Using PICOS to Ask Your Question

PICOS is an mnemonic for Patient Population or Problem, Intervention (treatment/test), Comparison (group or treatment), Outcomes, and Setting or Study type. PICOT is also used where the T stands for Time.

Various templates and web pages have been developed to help you frame your question. "Asking Answerable Questions" University of Illinois' page is one model. Melynik and Fineout-Overhold use:

Fill in the blanks with information from your clinical scenario:
THERAPY
In_______________, what is the effect of ________________on _______________ compared with _________________?

ETIOLOGY
Are ______________ who have _______________ at ______________ risk for/of ____________ compared with _____________ with/without ______________?

DIAGNOSIS OR DIAGNOSTIC TEST
Are (Is) ________________ more accurate in diagnosing _______________ compared with ____________?

PREVENTION
For ___________ does the use of _________________ reduce the future risk of ____________ compared with ______________?

PROGNOSIS
Does ____________ influence ______________ in patients who have _____________?

MEANING
How do _______________ diagnosed with _______________ perceive __________________?

Above information from "Evidence-based practice in nursing & healthcare: a guide to best practice" by Bernadette M. Melnyk and Ellen Fineout-Overholt. 2005, page 31.


Levels of Evidence

Quantitative Pyramid showing relative usefulness of different types of evidence to answer cause and effect questions.

Qualitative Pyramid showing relative usefulness of different types of evidence to answer meaning or experience questions.

Rating System for the Hierarchy of Evidence: Quantitative Questions

  • Level 1: Systematic review or meta-analysis of all relevant randomized controlled trials (RCTs), or evidence-based clinical practice guidelines based on systematic reviews of RCTs
  • Level 2: Evidence from at least one well-designed RCT
  • Level 3: Evidence from a well-designed controlled trial without randomization
  • Level 4: Evidence from well-designed case-control and cohort studies
  • Level 5: Evidence from systematic reviews of descriptive and qualitative studies
  • Level 6: Evidence from a single descriptive or qualitative study
  • Level 7: Evidence from the opinion of authorities and / or reports of expert committees
Above information from "Evidence-based practice in nursing & healthcare: a guide to best practice" by Bernadette M. Melnyk and Ellen Fineout-Overholt. 2005, page 10.


Finding Qualitative Research Articles

Strategies and Search Tips developed by the University of Washington librarians


Choose the Best Research Design to Answer the Question

ebp table 1

ebp table 2

Many different research designs exist, each with a specific purpose and with strengths and limitations. Try to choose the most rigorous one for your question. Below are two editorials that concisely outline this process. Access both online at the Consortium Library, or request them from AML.

Identifying the best research design to fit the question. Part 1. Quantitative Designs By Jackie Roberts. Evidence-Based Nursing, 2(1):4-6, 1999.
Identifying the best research design to fit the question. Part 2. Qualitative Designs. By Jenny Ploeg. Evidence-Based Nursing, 2(2):36-37, 1999.

Resources