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Oncology/Hematology Portal: EBM


Evidence-Based Medicine


Click this link to be taken to evidence-based resources that will help answer your clinical questions.

Critical Appraisal

Click this link to be taken to the resources that will help you critically appraise an article.

What is Evidence-Based Medicine?

“The conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence-based medicine requires the integration of individual clinical expertise with the best available external clinical evidence from systematic research and our patient's unique values and circumstances.”
-Centre for Evidence Based Medicine (CEBM), Toronto, CA

Glossaries of EBM terminology from reputable online resources:

Assess Assess the patient or problem to determine the pertinent issues.
Ask Ask a clear, answerable question to be pursued.
Acquire Acquire the evidence from an appropriate source.
Appraise Appraise the evidence to further examine its worth and reliability.
Apply Apply the evidence to the particular patient and their unique values and circumstances.


Formulating Clinical Questions

General questions or background questions ask for basic knowledge about an illness, disease, condition, test, process or thing. These types of questions typically ask who, what, where, when, how & why about things like a disorder, test, or treatment, etc.

For example

  • What is hairy cell leukemia?
  • What are the adverse effects of cisplatin?
  • What is the mechanism of action for dopamine agonists?
  • What are the common etiologies of sickle cell disease?
  • What are the diagnostic criteria for deep vein thrombosis?

These types of questions are best answered by medical textbooks, point-of-care tools (e.g. DynaMed Plus, Essential Evidence Plus, Lexicomp, OvidMD), and narrative review articles.

A well-built clinical foreground question should have at least 4 components. The PICO model is a helpful tool that assists you in organizing and focusing your foreground question into a searchable query.

P = Patient, Problem, Population (How would you describe a group of patients similar to you? What are the most important characteristics of the patient?)

I = Intervention, Prognostic Factor, Test, Exposure (What main intervention are you considering? What do you want to do with this patient? What is the main alternative being considered?)

C = Comparison (What is the main alternative to compare with the intervention? Are you trying to decide between two drugs, a drug and no medication,  placebo, or standard of care, or two diagnostic tests?)

O= Outcome (What are you trying to accomplish, measure, improve or affect? Outcomes may be disease-oriented or patient-oriented.)

 Use this chart to help determine the best study to search for during your literature search.

Type of Question


Study Design


An evaluation of a test, screening or other assessment such as history or physical exam

Prospective, blind comparison to a gold standard. RCT > controlled clinical trial (CCT) > cohort > case control > case series


An evaluation of a therapeutic or preventive intervention

RCT > CCT > cohort >case control > case series


An evaluation of clinical outcomes over time

cohort > case control > case series


An evaluation of a therapeutic, preventive, screening or diagnostic intervention, or a non-therapeutic exposure or behavior

cohort > case control > case series


An evaluation of the effectiveness of an intervention or exposure in preventing morbidity and mortality

RCT > CCT > cohort > case control > case series


An evaluation of cost versus benefit of a treatment or procedures

Economic analysis, cost-benefit analysis

Another element of the well-built clinical question to consider is the type of study (methodology). This information can be helpful in focusing the question and determining the most appropriate type of evidence.

                   Based on a design by Dahlgren Memorial Library, Georgetown University

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