How to read a guideline?

Associate Editor-In-Chief:

Any recommendations found on these pages are for education use only. Wikidoc is not a substitute for a licensed healthcare provider. Please see the disclaimers page for important information regarding limitations of the information found here. In recommending therapies, WikiDoc suggests that the following classification scheme be used. This is the classification scheme used by the ACC / AHA Guidelines Committee.

Use the Class designation to indicate whether the therapy is recommended or not and the certainty surrounding that recommendation. Use the Level of Evidence designation to indicate the strength of the data associated with that 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 A
Data derived from multiple randomized clinical trials or meta-analyses.

Level of Evidence B
Data derived from a single randomized trial, or non-randomized studies.

Level of Evidence C
Only consensus opinion of experts,case studies, or standard-of-care.