Strong | Consistent significant findings (≥75%) in studies of high quality, at least 2 studies |
Moderate | Consistent significant findings (≥75%) in studies of high and low quality with at least one study of high quality in the direction of consistent significant findings |
Weak | Significant findings of only one study of high quality or consistent significant findings (≥75%) in studies of low quality |
Inconclusive | Significant findings in less than 3 studies of low quality, or inconsistent significant findings (regardless of quality) |