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Module 3: Asking a Clinical Question

Asking the Question

Forming a Question -- PICO

To effectively search for the best evidence, you need to determine which details are most important to the situation at hand. The PICO formula helps clinicians extract the essential details and then re-configure them into a well-built clinical question.

A well-built clinical question needs to be directly relevant to the patient or problem at hand, and phrased in such a way as to facilitate the search for the answer. With PICO, this process is made easier! It helps formulate your search strategy by identifying the key concepts that need to be in the literature that can answer your question.

Components of PICO include:

Patient/population or problem
What are the most important characteristics of the patient? What is the primary compliant of the patient or patient group?

All of the following can be used to help define the population:

  • Age, race, and sex
  • Clinical setting
  • Comorbidities
  • Geographic location 

Intervention or variable of interest
What main intervention are you considering? What do you plan on doing for the patient? -- can include exposure to a disease, risk behavior, or prognostic factor.

Comparison
Is there a control or alternative strategy you would like to compare to the intervention? -- can include a placebo, an alternative strategy, or another prognostic factor.

Comparing against standard care or nothing (null) is also a potential option. 

Outcome
What are you trying to accomplish, measure, affect, or improve? -- can include risk of disease, accuracy of a diagnosis, or rate of occurrence of adverse outcome.

The goal of PICO is to focus your topic. Do not worry if your question does not fit perfectly into the PICO format. Your question can always be redefined and change.

Forming the Question -- Types of Questions

There are two types of clinical questions that you will encounter: background and foreground. Being able to identify the type of question will ultimately help when it comes to selecting resources.

Background

Questions that ask for general knowledge about a disorder, condition, diagnostic test, treatment/intervention, basic biology, or physiology. These types of questions typically ask who, what, where, why, when, and how. 

Examples 

  • What causes migraines?
  • What are the symptoms of poison ivy rash?
  • How do cancer cells grow and spread?
Foreground

Questions that ask for specific knowledge to make a clinical decision. They tend to be more specific and complex when compared tp background question. These questions usually concern a specific clinical situation or patient population. PICO is most commonly applied to reconfigure foreground questions into well-built questions.

Examples

  • In patients with osteoarthritis of the hip, is water therapy more effective than land-based exercise in restoring range-of-motion?
  • Is Crixivan effective in slowing the rate of functional impairment in a 45 year old male patient with Lou Gehrig's Disease?

Unlike background questions, foreground can be further categorized into different question types -- see the next tab to learn more!

Type of Questions

Foreground questions can fall into one of four categories:

Therapy
Determining the effects of interventions on patient-important outcomes

Prognosis
Estimating a patient's likely course over time to due factors other than interventions

Diagnosis
This category can include two types of questions

  1. Questions that establish the quality of a test to differentiate between those with and without a targeted condition or disease
  2. Questions of identification of a disorder in a patient presenting with specific symptoms.

Harm/Etiology
Determining the negative impact of an intervention or other exposure. Can also include questions for identifying causes for disease

Once you have determined our question it will become easier to:

  • Identify which research methodology or study design will provide the best evidence to answer your question
  • Select the best database to search for evidence
  • Select filters that will help narrow your search to appropriate results

Knowing the type of question can help you select the best study design to answer your question. You want to seek out the study design that will yield the highest level of evidence. 

Type of Questions  Type of Study
Therapy Randomized controlled trial > Cohort study > Case control > Case series
Prognosis Cohort study > Case control > Case series 
Diagnosis

Prospective, blind comparison to a gold standard* or Cross sectional study

Harm/Etiology Cohort study > Case control > Case series