Evidence-Based Practice in Nursing
Visit our PICO Research Question Resource Guide to learn more about formulating a PICO question.
What is Evidence-based Practice?
Evidence-based practice is the explicit use of current, best evidence in making clinical decisions regarding individual patient care. Evidence-based practice integrates:
- The best evidence from well-designed studies.
- A patient’s preferences or values.
- A clinician’s expertise from evidence gathered from the patient’s data.
Using evidence-based practice will help you make informed and personalized treatment decisions and deliver high quality health care to your patients.
Watch this video introducing evidence-based practice from the Iowa State University Library.
There are 5 steps used in the evidence-based processes. These 5 steps include:
- Ask: formulate an answerable clinical question.
- Acquire: search the literature to find the best evidence.
- Appraise: look at evidence for its value and usefulness.
- Apply: integrate the results into your clinical practice.
- Assess: evaluate the effectiveness of the outcomes.
How do I Formulate a Clinical, or PICO, Question?
Knowing how to form a PICO question is important for finding evidence that supports your clinical practices. A PICO question focuses the scope of your results and helps you develop keywords to search for evidence. Watch this video to learn more about why PICO questions are important. Also, visit our PICO Research Question Resource Guide to learn more about formulating a PICO question.
Ask background questions and foreground questions to learn more about your clinical question.
questions provide the basics for a greater grasp of the concepts. These are
typically found in textbooks, encyclopedia, or reviews.
- Not normally asked when clinical decisions are needed to be made about a patient
questions provide specific knowledge to inform clinical decisions. These
are typically found in journals and conference proceedings.
- Require a grasp of the basic concepts from background questions
Think about inclusion and exclusion criteria to help you select and set boundaries for your searching.
- Inclusion: Elements that must be present
to be eligible for inclusion. For example:
- Certain types of studies, certain geographic locations, published within last 5 years, comparison of certain treatments
- Exclusion: Elements that disqualify the
study from inclusion. For example:
- Use of wrong types of studies, published more than 5 years ago, published in another language (depending on if you can read the language or are looking for articles only pertaining to the U.S.)
Where do I Search for Literature?
The following nursing databases are recommended to search for evidence-based articles:
- Check the “Evidence-Based Practice” filter in the Limit Your Results box
- Narrow down results to “Meta-analyses”, “Systematic Reviews”, or “Randomized Controlled Trials” in the Publication Type filter in the Limit Your Results box.
- After searching your results, choose the Cochrane Reviews tab in the results section to find Meta-analyses and Systematic Reviews.
- After searching your results, choose the Trials tab in the results section to find Randomized Controlled Trials, Cohort Studies, and Control Studies.
- Take a look at our Cochrane PICO Search Beta tips on our PICO Research Questions Resource Guide
- Add “AND meta-analysis”, “AND randomized controlled trial”, or “AND systematic[sb]” to your search to find these types of articles.
- Click on the Clinical Queries link (under the Find heading) at the bottom of the homepage to limit your results to clinical studies or systematic reviews. (PubMed Clinical Queries)
What Types of Evidence is Needed?
Evidence Pyramids rank research types based on the rigor of evidence provided in the study. High level evidence from the top of the pyramid is preferred but may not be available for all questions. The type of questions that you are asking determines which types of studies are most appropriate.
Watch this video to find out more about the types of literature in the Evidence Pyramid.
|Filtered Information (Secondary Literature)|
|Meta-analysis||Systematic reviews that use quantitative methods to summarize results.|
|Systematic Review||Rigorous method of identifying, critically appraising, and synthesizing literature for a specific topic.|
|Critically Appraised Topic and Articles||Evaluation/synthesis of multiple research studies or of an individual research article.|
|Unfiltered Information (Primary Literature)|
|Randomized Controlled Trials (RCTs)||Randomized group of patients in experimental and control groups. Followed up for variables/outcomes of interest.|
|Cohort Study||Two groups of patients that received exposure or did not, followed forward for outcome of interest.|
|Case-Control Study||Comparison of patients with outcome of interest and control patients without outcome to see if they had exposure of interest.|
|Background Information||Handbooks, encyclopedias, textbooks that provide good foundation or introduction to topic.|
Different types of clinical questions can be best answered by different types of research studies. If you cannot find a study with the highest level of evidence, work your way down the Evidence Pyramid until you find a study on your topic. Here are study designs best suited to each type of clinical question:
|Clinical Question||Suggested Research Design|
|All Clinical Questions||Systematic review, meta-analysis|
|Therapy||Randomized controlled trial, meta-analysis|
|Etiology||Randomized controlled trial, meta-analysis, cohort study|
|Diagnosis||Randomized controlled trial|
|Prevention||Randomized controlled trial, meta-analysis|
|Quality Improvement||Randomized controlled trial|
How do I Appraise My Literature?
Keep the following criteria in mind when you are appraising your literature:
- Validity: Look for trials that mimic
clinical practice with outcomes that make sense. The outcomes should be large,
useful, and statistically significant.
- Did the experiment demonstrate a cause-effect relationship between the independent and dependent variables?
- Reliability: Examine the numerical data
reported for trials to see if they have large numbers of patients to avoid the
random chance that leads to wrong outcomes.
- Are the results of the experiment replicable in clinical practice? Is the research methodology described in detail so the experiment can be repeated
- Applicability: Evaluate the study’s
patients in comparison with the patients that the evidence will be applied to.
Watch this video to learn more questions to ask during evidence appraisal. Or use these evidence tools to appraise your research article:
The following online resources are recommended for learning more about evidence-based practice:
- Agency for Healthcare Research and Quality - Grants, funding, and guidelines/measures for research in healthcare.
- The Centre for Evidence-based Medicine - Tools and research for evidence-based effective healthcare.
- Duke University Evidence-based Practice Tutorial - Interactive tutorial for all steps of evidence-based practice, but mainly focusing on appraisal.
- National Institute of Nursing Research - Research, training, and information on nursing research.
- Northern Virginia Community College EBP Search Process Checklist - Worksheet/checklist for creating and PICO questions, searching for studies, and appraising articles.
- Johns Hopkins Nursing Evidence-Based Practice Question Development Tool - Worksheet for creating a PICO question.
- Loma Linda University PICO Clinical Scenarios - Multiple clinical scenarios to help you learn how to formulate a PICO question.
- PubMed PICO Question Generator - Interactive PICO question generator.