Table 6.3Summary of strength of evidence for recommendations

Strength-of-evidence classificationCriteria
Strength of Evidence = AMultiple well-designed randomized clinical trials, directly relevant to the recommendation, yielded a consistent pattern of findings.
Strength of Evidence = BSome evidence from randomized clinical trials supported the recommendation, but the scientific support was not optimal. For instance, few randomized trials existed, the trials that did exist were somewhat inconsistent, or the trials were not directly relevant to the recommendation.
Strength of Evidence = CReserved for important clinical situations in which the Panel achieved consensus on the recommendation in the absence of relevant randomized controlled trials.

From: 6, Evidence and Recommendations

Cover of Treating Tobacco Use and Dependence: 2008 Update
Treating Tobacco Use and Dependence: 2008 Update.
Tobacco Use and Dependence Guideline Panel.

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