Table 2 GRADE Quality of evidence and strength of recommendations

High-quality evidence, strong recommendation

Desirable effects clearly outweigh undesirable effects or vice versa

Consistent evidence from well-performed RCTs or exceptionally strong evidence from unbiased observational studies

Recommendation can apply to most patients in most circumstances. Further research is unlikely to change our confidence in the estimate effect

Moderate quality evidence, strong recommendation

Desirable effects clearly outweigh undesirable effects or vice versa

Evidence from RCTs with important limitations (inconsistent results, methodological flaws, indirectness, imprecision) or exceptionally strong evidence from unbiased observational studies

Recommendation can apply to most patients in most circumstances. Further research (if performed) is likely to have an important impact on our confidence in the estimate of effect and may change the estimate

Low-quality evidence, strong recommendation

Desirable effects clearly outweigh undesirable effects or vice versa

Evidence for at least one critical outcome from observational studies, RCTs with serious flaws or indirect evidence

Recommendation may change when higher quality evidence becomes available. Further research (if performed) is likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate

Very low-quality evidence, strong recommendation (rarely applicable)

Desirable effects clearly outweigh undesirable effects or vice versa

Evidence for at least one critical outcome from unsystematic clinical observations or very indirect evidence

Recommendation may change when higher quality evidence becomes available; any estimate of effect for at least one critical outcome is very uncertain

High-quality evidence, weak recommendation

Desirable effects closely balanced with undesirable effects

Consistent evidence from well-performed RCTs or exceptionally strong evidence from unbiased observational studies

The best action may differ depending on circumstances or patients or societal values. Further research is unlikely to change our confidence in the estimate effect

Moderate quality evidence, weak recommendation

Desirable effects closely balanced with undesirable effects

Evidence from RCTs with important limitations (inconsistent results, methodological flaws, indirectness, imprecision) or exceptionally strong evidence from unbiased observational studies

Alternative approaches likely to be better for some patients under some circumstances. Further research (if performed) is likely to have an important impact on our confidence in the estimate of effect and may change the estimate

Low-quality evidence, weak recommendation

Uncertainty in the estimates of desirable effects, harms, and burden; desirable effects, harms, and burden may be closely balanced

Evidence for at least one critical outcome from observational studies, RCTs with serious flaws or indirect evidence

Other alternatives may be equally reasonable. Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate

Very low-quality evidence, weak recommendation

Major uncertainty in the estimates of desirable effects, harms, and burden; desirable effects may or may not be balanced with undesirable effects

Evidence for at least one critical outcome from unsystematic clinical observations or very indirect evidence

Other alternatives may be equally reasonable. Any estimate of effect, for at least one critical outcome, is very uncertain