| High: |
 | High confidence that the evidence reflects the true effect. Further research is very unlikely to change our confidence in the estimate of effect. |
| Moderate: |
 | Moderate confidence that the evidence reflects the true effect. Further research may change our confidence in the estimate of effect and may change the estimate. |
| Low: |
 | Low confidence that the evidence reflects the true effect. Further research is likely to change the confidence in the estimate of effect and is likely to change the estimate. |
| Insufficient: |
 | Evidence either is unavailable or does not permit a conclusion. |
From: Recurrent Nephrolithiasis in Adults: Comparative Effectiveness of Preventive Medical Strategies
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