Table 1.
Grading of Recommendations, Assessment, Development, and Evaluation quality assessment criteria (6)
| Study design | Quality of evidence | Factors lowering quality of evidence | Factors increasing quality of evidence |
|---|---|---|---|
|
| |||
| Randomized trial | High | Imprecision of
estimate Risk of bias Inconsistency of data Indirectness of evidence Likely publication bias |
Dose-response
gradient Large effect of intervention If plausible confounding would reduce effector suggest a spurious effect when reported results show no effect |
| Moderate | |||
| Observational study | Low | ||
| Very low | |||