Evidence-Based Rating System Used to Determine Strength of Recommendations

Strength of recommendation
    AStrong evidence for efficacy and substantial clinical benefitStrongly recommended
    BStrong or moderate evidence for efficacy, but only limited clinical benefitGenerally recommended
    CInsufficient evidence for efficacy, or efficacy does not outweigh possible adverse consequencesOptional
    DModerate evidence against efficacy or for adverse outcomeGenerally not recommended
    EStrong evidence against efficacy or for adverse outcomeNever recommended
Quality of evidence supporting recommendation
    IEvidence from at least 1 well-executed randomized, controlled trial or 1 rigorously designed laboratory-based experimental study that has been replicated by an independent investigator
    IIEvidence from at least 1 well-designed clinical trial without randomization; cohort or case-controlled analytic studies (preferably from more than 1 center); multiple time-series studies; dramatic results from uncontrolled studies; or some evidence from laboratory experiments
    IIIEvidence from opinions of respected authorities based on clinical or laboratory experience, descriptive studies, or reports of expert committees
  • Adapted with permission from Centers for Disease Control and Prevention. Guidelines for the prevention and treatment of opportunistic infections among HIV-exposed and HIV-infected children: recommendations from CDC, the National Institutes of Health, the HIV Medicine Association of the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the American Academy of Pediatrics. MMWR Recomm Rep. 2009;58(RR-11):1–166.