Table 2.

Level of Recommendation

Level of Recommendation	Evidence Level	Implied Obligation
Essential practice: Panel members are confident the benefits of the recommended approach clearly exceed the harms (or, in the case of a negative recommendation, that the harms clearly exceed the benefits).	In general, high or moderate-quality evidence (Table 1) or lesser evidence or expert opinion when high-quality evidence is impossible to obtain and the anticipated benefits strongly outweigh the harms.	In general, healthcare personnel and facilities “should” implement the recommended approach unless a clear and compelling rationale for an alternative approach is present.
Additional approach: Panel members have determined that the benefits of the recommended approach are likely to exceed the harms (or, in the case of a negative recommendation, that the harms are likely to exceed the benefits).	• In general, may be supported by either low-, moderate-, or high-quality evidence. • There is high-quality evidence, but the benefit–harm balance is not clearly tipped in one direction. • The evidence is weak enough to cast doubt on whether the recommendation will consistently lead to benefit. • The likelihood of benefit for a specific patient population or clinical situation is extrapolated from relatively high-quality evidence demonstrating impact on other patient populations or in other clinical situations (eg, evidence obtained during outbreaks used to support probable benefit during endemic periods). • The impact of the specific intervention is difficult to disentangle from the impact of other simultaneously implemented interventions (eg, studies evaluating “bundled” practices). • There appears to be benefit based on available evidence, but the benefit/harm balance may change with further research. • Benefit is most likely if the intervention is used as a supplemental measure in addition to essential practices.	Healthcare personnel and facilities “could,” or “may consider” implementing the recommended approach. The degree of appropriateness may vary depending on the benefit–harm balance for the specific setting.
Unresolved issue: Panel members agree that there is both a lack of pertinent evidence and unclear balance between benefits and harms.