Skip to Main Content

Evidence-Based Medicine: Question Types and Corresponding Resources

Foreground and Background Questions

Clinical questions are categorized as background or foreground. Once you determine your question type, consult the box called "What Resources Should I Use?" (below) to find the appropriate resources for answering your question. 

Background Questions

  • Ask to obtain general knowledge about an illness, condition, or disease. 
  • Ask who, what, when, where, how, or why

Foreground Questions

  • AKA Clinical Questions
  • Ask for specific knowledge to inform clinical decisions. 
  • Deal with specific patient or population; more complex than background questions. 

What Resources Should I Use?

For background questions:

  • Medical textbooks
  • Review articles (e.g. Annals "In the Clinic", American Family Physician, Nature Disease Primers, etc.)
  • Point of care tools and applications (e.g. DynaMed)

For foreground questions:

Clinical Question Types and Study Design

Foreground questions can be further classified into four groups: therapy, diagnosis, prognosis, and etiology/harm. Certain study designs are better for answering particular question types. The Appropriate Study Designs column lists the study designs best suited to each question type, in order of utility.

Question Type Definition Appropriate Study Designs Possible Question Frameworks
Therapy Questions about the effectiveness of treatment in order to achieve an outcome (drugs, surgical intervention, exercise, counseling, etc.) Randomized Controlled Trial (RCT)



Diagnosis Questions about identification of a disorder in a patient presenting with specific symptoms

RCT > Cohort Study



Prognosis Questions about the progression of a disease or outcome of a patient with a particular condition

Cohort Study >

Case Control Studies >

Case Series




Etiology/Harm Questions about the negative impact from an intervention or other procedure 

Cohort Study >

Case Control Studies >

Case Series