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Nursing: EBP-Crash Course

EBP-Crash Course

EBP-Crash Course

 Excerpt from Evidence-Based Practice Workbook, 2nd ed. by Paul Glasziou, Chris Del Mar and Janet Salisbury.  Blackwell, 2007.

evidence based practice

 Convert information needs into focused questions:

  •  You may wish to use the PICO model (linked below) to    define a clear clinical question that incorporates the Patient/problem, Intervention,Comparison, and Outcome.
    • Efficiently track down the best evidence with which to answer the question:
  • Select a database in which to start (see our recommended list of EBP databases, linked below)
  • After searching, refine your results as needed using limiters. As shown in the pyramid of evidence to the left, certain types of literature are considered most useful in answering clinical questions. Many databases allow you to limit results by study type.
  • Critically appraise the evidence for validity and clinical usefulness.
  • Apply the results in clinical practice.
  • Evaluate performance of the evidence in clinical application.

 *Adapted from UIC University Library's Evidence Based Medicine research guide.



Developing Your Question Using PICO

PICO is an acronym for

  • Patient
  • Intervention
  • Comparison
  • Outcome

PICO is used to create a researchable question based on a clinical situation you have encountered.  Based on your PICO question, you will identify keywords and/or subject terms to use in database searches. 

You can use PICO to develop your clinical question.

P - Patient or population/disease: Which population are you studying? (Consider age, gender, ethnicity, group with a certain disorder, etc.)

I - Intervention, prognostic factor, or exposure: What do you want to do for the patient? (Consider therapy, exposure to a disease, risk behavior, prognostic factor, preventative measure, or diagnostic test)

C - Comparison or control: Are you comparing two interventions or variables? (Consider absence of disease, absence of risk factor, or use of placebo)

O - Outcome: What is the expected result or what do you hope to accomplish, improve or affect? (Consider disease incidence, accuracy of a diagnosis, rate of occurrence of adverse outcome, survival or mortality rates)What is the expected result or what do you hope to accomplish, improve or affect? (Consider disease incidence, accuracy of a diagnosis, rate of occurrence of adverse outcome, survival or mortality rates)

Types of Evidence and Study Designs

Consider the level of evidence you need. You can search for specific types of evidence or study designs such as randomized controlled trials or systematic reviews.

Pyramid of Evidence

Pyramid of Evidence. Source: “EBM Pyramid.” Digital Image. Eli M. Oboler Library, 27 May 2016.

Source: “EBM Pyramid.” Digital Image. Eli M. Oboler Library, 27 May 2016.

Filtered Information (secondary literature)

Systematic review
Uses explicit, rigorous methods to identify, critically appraise, and synthesize relevant studies

Meta analysis
A quantitative method of combining the results of independent studies and synthesizing summaries and conclusions which may be used to evaluate therapeutic effectiveness.

Critically Appraised Topic
A summary of the current best evidence on a topic, generally by topic experts. Critically appraised topics (CAT's) usually include evidence from more than one study, but are more brief and their methods less rigorous than systematic reviews.

Critically Appraised Individual Article (a.k.a. Critically Appraised Paper)
A summary of a single paper, generally by a topic expert.

Unfiltered Information (primary literature)

Randomized controlled trial
A clinical trial that involves at least one test treatment and one control treatment, concurrent enrollment and follow up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process

Cohort study
Study in which subsets of a defined population are identified.

Case control trial
Study which start with the identification of persons with a disease of interest and a control group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.

Clinical trial
Pre-planned studies of the safety, efficacy or optimum dosage schedule of one or more diagnostic, therapeutic or prophylactic drugs, devices or techniques, selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects.



Use PICO to formulate your search strategy. Select terms used to develop your clinical question using PICO. Begin by searching the patient problem and intervention. For this example, the patient problem is diabetes, and the intervention is nutrition counseling. Enter both terms in CINAHL or another Nursing/Allied Health Database search box. Combine your terms using the Boolean operator AND. Using AND to combine terms tells the database to look for both terms in the title and abstract of the resources indexed in a database.

CINAHL Complete is is the WWCC's premier research tool
for Nursing & Allied Health journals and one of the definitive tools
you will likely find yourself using for the rest of your academic career and professional career.


Access to both CINAHL and Medline

MEDLINE-Created by the United States
National Library of Medicine,
MEDLINE is an authoritative database 
for biomedical and health journals used by 
health care professionals, nurses, clinicians and researchers.


Appraise and Apply


When reading an article, report, or other summary of a research study, there are two principle questions to keep in mind:

1. Is this relevant to my patient or the problem?

  • Once you begin reading an article, you may find that the study population isn't representative of the patient or problem you are treating or addressing. Research abstracts alone do not always make this apparent.
  • You may also find that while a study population or problem matches that of your patient, the study did not focus on an aspect of the problem you are interested in. E.g. You may find that a study looks at oral administration of an antibiotic before a surgical procedure, but doesn't address the timing of the administration of the antibiotic.
  • The question of relevance is primary when assessing an article--if the article or report is not relevant, then the validity of the article won't matter (Slawson & Shaughnessy, 1997).

2. Is the evidence in this study valid?

  • Validity is the extent to which the methods and conclusions of a study accurately reflect or represent the truth. Validity in a research article or report has two parts: 1) Internal validity--i.e. do the results of the study mean what they are presented as meaning? e.g. were bias and/or confounding factors present?; and 2) External validity--i.e. are the study results generalizable? e.g. can the results be applied outside of the study setting and population(s)?
  • Determining validity can be a complex and nuanced task, but there are a few criteria and questions that can be used to assist in determining research validity. The set of questions, as well as an overview of levels of evidence, are below.

For a checklist that can help you evaluate a research article or report, use our checklist for Critically Evaluating a Research Article


Remember to Use APA!

Purdue University Online Writing Lab (OWL)

These OWL resources will help you learn how to use the American Psychological Association (APA) citation and format style. Authoritative resources on in-text citation and the References page, as well as APA sample papers, slide presentations, and the APA classroom poster.