Table 2.
Strength of Conclusion.
| Level | Conclusion Based on |
|---|---|
| 1 | A1 study or ≥2 A2-level studies |
| 2 | One A2-level study or ≥2 independent B-level studies |
| 3 | One B-level or C-level study |
| 4 | Inconclusive or inconsistent results between various studies |
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