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Evidence-Based Practice Guide


The importance of asking the "right" question cannot be overemphasized. There are two types of clinical questions: background and foreground.  While recognizing the difference between the two types of questions can be a challenge, understanding these differences is critical as it impacts the search approach, applicable information resources, and the searcher’s time.

—Sources: Guyatt, 2015, Melnyk & Fineout-Overholt, 2005; Straus, 2011.

These questions ask for general knowledge about a condition, test, or treatment and can be answered with textbooks or review articles. They have two essential components:

  • A question root (who, what, how, why) and a verb
  • A disorder, test, treatment or other aspect of healthcare

Example: What is mindfulness therapy?
This question can be answered in a psychotherapy textbook, review articles, and online synthesized resources, such as UpToDate. Time may be lost if the researcher or clinician does not realize that the question is looking for general knowledge and is searching for published studies instead of textbooks.

—Sources: Guyatt, 2015, Melnyk & Fineout-Overholt, 2005; Straus, 2011.

Foreground questions form the essence of evidence-based practice and encompass diagnosis, treatment/prevention, etiology/harm, prognosis. They can be answered from scientific research/evidence.

Example: In hospital staff, does mindfulness therapy reduce stress?
This question builds on the background knowledge of mindfulness therapy. The answer may be found in a published study that compares mindfulness therapy with either a control or no intervention.

A well-defined and focused question is comprised of parts. Using a standardized format or framework helps organize the parts of the question and identify key concepts. The PICO mnemonic concept – introduced in 1995 by Richardson, et. al. – was developed to help answer health-related foreground questions by breaking down the question into searchable keywords. Over the years, the framework has evolved to include additional components, such as "T" (Timeframe), "TT" (Type of question + Type of study design). In the UT Southwestern PICO(M) framework, "M" refers to methodology or study design. —Sources: Davies, 2011; Richardson, Wilson, Nishikawa, & Hayward, 1995

Patient, Population,
or Problem
 P  What is the important patient problem or condition?
How would you describe the important characteristics of the patient?
or Indicator
I What do you want to do to help the patient?
Do you want to consider a specific treatment, diagnostic test, or exposure?
Is there a prognostic factor that might affect the outcome of the condition?
or Control
C What are the choices of intervention, if any?
Are you trying to decide between two different therapies or two different tests?
Between a therapy or no therapy (placebo)?
Between a new therapy and the standard of care?
Outcome O What are you trying to achieve with the intervention?
What is the important outcome for the patient?
Methodology  M  What is the best study design or methodology for the type of question you are asking?

—Sources: Guyatt, 2015, Melnyk & Fineout-Overholt, 2005; Straus, 2011.

Using PICO(M) or another standardized framework helps organize the parts of the question and identify key concepts.

  • Helps you ask answerable questions
    • Clarifies the question
    • Identifies what information is needed to answer the question
  • Helps you find the evidence
    • Translates your question into search terms
    • Develops an effective search strategy
  • Helps you perform better, quicker searches

—Sources: Guyatt, 2015, Melnyk & Fineout-Overholt, 2005; Straus, 2011.

The following table summarizes the types of quantitative questions as well as the associated study design(s) to answer the question. The sample question templates can be used as a starting point to frame the PICO question. Based on the research topic/clinical problem, the PICO template may need to be modified and may not include all components. (Cullen, 2018; Health Evidence, 2009; Greenhalgh, 2001; Guyatt, 2015; Melnyk, 2005)

Type Focus and Question Template Characteristics Methodology

Determine the effect of therapy/intervention (i.e., drug treatment, surgical procedure, education) on outcome(s) (i.e., symptoms, function, costs, morbidity, etc.).

In patients with type 2 diabetes (P), what is the effect of sitagliptin (I) on glycemic control (O) compared with placebo (C)?

In ___________(P), what is the effect of __________(I) on __________(O) compared with __________(C)?

Involves choosing or comparing treatments

Often compares two drugs/therapies

Largest volume of questions


Systematic Reviews

Randomized Controlled Trials


Identify risk factors that if adjusted can help reduce the chance of developing the disease.

In elderly patients (P), what is the risk of pneumonia (O) in patients who receive the influenza vaccine (I) compared with elderly patients who are not vaccinated (C)?

In ___________(P), what is the risk of __________(O) in __________(O) compared with __________(C)?

Involves choosing or comparing treatments

Often compares two drugs/therapies


Systematic Reviews

Randomized Controlled Trials


Demonstrate whether a diagnostic test is valid and reliable, in order to confirm or exclude a diagnosis.

In young children with middle ear effusion, is microtympanometry (I) more accurate compared to medical history and otoscopy (C) in diagnosing hearing loss (O)?

In __________ with __________(P), are (is) __________(I) more accurate in diagnosing __________(O) compared with __________(C)?

Involves choosing, confirming, and comparing diagnostic tests

Concerned with sensitivity and specificity

Cross-sectional studies


Determine the effects of a potentially harmful agent on outcomes.

Are patients with restless legs syndrome (P) who take dopamine agonists(I) at risk for compulsive gambling (O)?

Are __________(P) who __________(I) at __________risk for/of __________(O) compared with __________ with/without __________(C)?

Risk or causality are key concepts

Questions about negative impact from an intervention or exposure

Cohort Studies

Case Reports


Estimate a patient’s clinical course over time and anticipate probable complications of the disorder

In patients with no motor response (P) three days following a hypoxic coma after a cardiac arrest (I), what is the chance of good neurological recovery (O)?

In __________ with __________(P), does __________(I) influence __________(O) versus __________(C)?

Concerned with the anticipated clinical course of a disease

Relapse, mortality, or survival rate can be key concepts

Cohort Studies

(Health Evidence, 2009; Guyatt, 2015; Wessel, 2019)

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