ESC Guidelines Classification Scheme

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

The Class designation is used to indicate whether a therapy is recommended or not and the certainty surrounding that recommendation.

Classes of Recommendation

Class I:

Conditions for which there is evidence and/or general agreement that a given procedure or treatment is beneficial, useful, and effective.

Class II:

Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness/efficacy of a procedure or treatment.

Class IIa:

Weight of evidence/opinion is in favor of usefulness/efficacy.

Class IIb:

Usefulness/efficacy is less well established by evidence/opinion.

Class III

Conditions for which there is evidence and/or general agreement that a procedure/treatment is not useful/effective and in some cases may be harmful.

Level Of Evidence

Level of Evidence A:

Data derived from multiple randomized clinical trials or meta-analyses of such studies.

Level of Evidence B:

• Data derived from one or more randomized trials or meta-analysis of such studies.
• Data derived from one or more non-randomized trials or meta-analysis of such studies.

Level of Evidence C:

• Non randomized observational studies with limitations in design or execution or Metanalysis of such studies.
• Consensus opinion of experts based on clinical experience.

Applying Classification of Recommendations and Level of Evidence

2016 Classification of Recommendations and Level of Evidence