Resources for: Evidence-Based Practice (EBP)

• The 5 Steps of EBP
• Asking the Question
• Evidence Hierarchy
• Acquiring the Evidence
• Appraising the Evidence
• Additional Resources

Use the five "A's" to remember the critical steps of the evidence-based practice process:

ASK the answerable clinical question.

ACQUIRE the most relevant and best evidence to answer the question.

APPRAISE the evidence critically for validity, relevance, and applicability.

APPLY the evidence, along with critical expertise and the patient's preferences and values.

ASSESS the effectiveness and efficiency of the previous four steps and seek ways to improve one's ability to ask, acquire, appraise, and apply.

This guide covers the first 3 steps.

The "Well-Built Clinical Question"

PICO(T)

The first part of any research is identifying the question you want to answer. This is very important because the more you understand your question the more likely you are to obtain relevant results. The process of formulating a good search question is known in evidence-based health care as “the well-built clinical question.”* One way of building your search question starts with the patient and is known as PICO, which stands for:

• P - Patient or Population or Problem/Disease
  • Who or what is the question about? This may include the primary problem, disease, or circumstances. Sometimes the sex, age, or race of a patient might be relevant to the diagnosis or treatment of a disease.
• I - Intervention, Exposure or Prognostic Factor
  • What main intervention/treatment are you considering? What factor may influence the prognosis of the patient, such as age or comorbidities? What was the patient exposed to?
• C - Comparison(s) or Control
  • What alternative intervention are you considering, if any? For example, you might be comparing the efficacy of two medications or the accuracy of two diagnostic tests. Your clinical question does not have to always have a specific comparison.
• O - Outcome(s)
  • What are you trying to accomplish or measure? What are you trying to do for the patient or problem? Examples might include managing a disease, alleviating symptoms, preventing a disease, etc.
• T - Timeframe (optional)
  • What's the amount of time that you'll be observing the patient or problem. For example, improving rates of hospital-acquired infections over the course of a year.

Also consider the two Ts

Type of Question

• Diagnosis : How to select and interpret diagnostic tests
• Therapy : How to select treatments to offer patients that do more good than harm and that are worth the efforts and costs of using them
• Prognosis : How to estimate the patient’s likely clinical course over time and anticipate likely complications of disease
• Etiology : How to identify causes for disease, including genetics

Type of Study

The evidence hierarchy pyramid is a visual representation of the strength of different research study designs. It can be helpful to think about evidence as a pyramid – not all study designs and resource types are created equal.

Filtered Information

At the top of the pyramid, we have filtered information – this includes systematic reviews, meta-analyses, and evidence syntheses; practice guidelines; and critically-appraised topics found in clinical resources. This type of information has used a high-quality methodology to synthesize primary resources – meaning that they have searched for available primary literature and evaluated its validity to provide answers to specific clinical questions. It is important to remember that the quality and reliability of filtered information can only be as good as the primary literature it includes.

Unfiltered Information

In the middle of the pyramid, we have unfiltered information – this is known as primary literature. These are individual experimental study designs. A randomized controlled trial is considered the highest quality individual study design, followed by cohort studies and case-controlled studies. We will discuss these study designs in more detail later in the tutorial.

Background Information

At the base of the pyramid, we have background information and expert opinion. Background information is not typically used in making complex clinical decisions, but can be helpful in defining parts of your clinical question.

Synthesized resources

Start with:

Primary article databases

Then try these:

Clinical Practice Guidelines

Also consider these specialized resources:

Books

Toolkits

Tutorial