Table 4.4

GRADE System, As Adapted by ACCP

Grade of RecommendationBenefit vs Risk and BurdensMethodologic Quality of Supporting EvidenceImplications
Strong recommendation, high-quality evidence, Grade 1ADesirable effects clearly outweigh undesirable effects, or vice versaConsistent evidence from RCTs without important limitations or exceptionally strong evidence from observational studiesRecommendation can apply to most patients in most circumstances; further research is very unlikely to change our confidence in the estimate of effect
Strong recommendation, moderate-quality evidence, Grade 1BDesirable effects clearly outweigh undesirable effects, or vice versaEvidence from RCTs with important limitations (inconsistent results, methodologic flaws, indirect or imprecise), or very strong evidence from observational studiesRecommendation can apply to most patients in most circumstances; higher quality research may well have an important impact on our confidence in the estimate of effect and may change the estimate
Strong recommendation, low or very low-quality evidence, Grade 1CDesirable effects clearly outweigh undesirable effects, or vice versaEvidence for at least one critical outcome from observational studies, case series, or from RCTs with serious flaws or indirect evidenceRecommendation can apply to most patients in many circumstances; higher-quality research is likely to have an important impact on our confidence in the estimate of effect and may well change the estimate
Weak recommendation, high-quality evidence, Grade 2ADesirable effects closely balanced with undesirable effectsConsistent evidence from RCTs without important limitations or exceptionally strong evidence from observational studiesThe best action may differ depending on circumstances or patient or society values; further research is very unlikely to change our confidence in the estimate of effect
Weak recommendation, moderate-quality evidence, Grade 2BDesirable effects closely balanced with undesirable effectsEvidence from RCTs with important limitations (inconsistent results, methodologic flaws, indirect or imprecise), or very strong evidence from observational studiesBest action may differ depending on circumstances or patient or society values; higher-quality research may well have an important impact on our confidence in the estimate of effect and may change the estimate
Weak recommendation, low or very low-quality evidence, Grade 2CDesirable effects closely balanced with undesirable effectsEvidence for at least one critical outcome from observational studies, case series, or from RCTs with serious flaws or indirect evidenceOther alternatives may be equally reasonable; higher-quality research is likely to have an important impact on our confidence in the estimate of effect and may well change the estimate

Reproduced from Guyatt et al. (17).

  • We use the wording we recommend for strong (Grade 1) recommendations and we suggest for weak (Grade 2) recommendations. ACCP indicates American College of Chest Physicians; GRADE, Grading of Recommendations Assessment, Development and Evaluation; and RCTs, randomized controlled trials.