Defining Evidence Based Medicine

Defining Evidence Based Medicine

Blog in Health relies on a central concept, the concept of Evidence Based Medicine (EBM) or evidence-based medicine in French. This concept was developed by epidemiologists of McMaster University in Canada in 1980 (Sackett et al., 2000). It calls for all medical decision based on theoretical knowledge, judgment and experience but also on scientific evidence (Sackett et al., 2000). The notion of proof is a knowledge from clinical research conducted in the field of treatment of diseases and which are based on valid and applicable in current medical practice results.

Gradation of levels of evidence

Clinical studies are considered randomized controlled trials, meta-analyzes, cross-sectional studies, cohort studies and case-control studies well built (Sackett et al., 2000). Reviews of the effectiveness of an intervention are classified according to the level of evidence:

– A level, the best (meta-analysis from data from randomized controlled trials, randomized controlled trials with a narrow confidence index and follow-up greater than 80%)

– Level B (systematic review of cohort studies, individual cohort study or randomized controlled trials with follow-up less than 80%)

– Level C (systematic review of case-control studies, case-control study of quality) and D (case series, cohort or case control study)

– The level E, the worse (expert opinion or scoping study).

The general message

Evidence Based Medicine encourages the development of intervention studies that verify the effectiveness of therapeutic strategies and actions to prevent health. Nobody is supposed to ignore the impact that could have a product on their health and quality of life. Medical decision to use, outstanding risks and expected benefits are better defined.

What it means for Health Professionals

Evidence Based Medicine is based on three main principles (Sackett et al., 2007.)

– Rigorous, explicit and judicious use of current best evidence in decision making for the treatment of individual patients,

– The need to include patient choice in the decision process,

– Clinical expertise without which the practice could fall under the tyranny of the evidence, since even the most excellent external evidence may be inapplicable or inappropriate to a patient.

What it means for Researchers

The randomized controlled trial of major significance in this logical demonstration. This is the most powerful method for this proof strength. Pus in addition to learned societies and health authorities are using the reading grid Evidence Based Medicine to issue their recommendations on each intervention with a target population. This evidence does not replace the judgment and experience, they complement (Sackett et al., 2000). They facilitate the monitoring of recent innovations by practitioners.

What it means for Policymakers

Current Evidence Based Medicine is now declined in several therapeutic disciplines applied. It has several interests, updating knowledge in areas that are progressing rapidly on a global scale, comparison of the effectiveness of interventions, increased confidence in decision teams clinical decision, standardization of best practices interventional the rationalization of resources based on an assessment in a quality approach, a better understanding, a more critical sense of the methods used in clinical research, more precise targeting of objectives, and finally, improved communication intra and inter team as with the patient and family.


Sackett DL, Rosenberg WM, Gray JA, Haynes RB, Richardson WS (2007). Evidence based medicine: what it is and what it isn’t. Clinical Orthopedic Related Research, 455, 3-5.

Sackett DL, Straus SE, Richardson WS, Rosenberg W, Haynes RB (2000). Evidence-Based Medicine: how to practice and teach EBM. London: Churchill Livingstone.

To reference this Blog en Sante © article.

Ninot G (2014). Definition of Evidence Based Medicine. Blog en Sante, L5.

© Copyright 2014 Grégory Ninot. All rights reserved.