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Grade of recommendation & criteria
| Grade | Descriptor | Qualifying Evidence |
|---|---|---|
| A | Strong recommendation | Level I evidence or consistent findings from multiple studies of levels II, III, or IV |
| B | Recommendation | Levels II, III, or IV evidence and findings are generally consistent |
| C | Option | Levels II, III, or IV evidence, but findings are inconsistent |
| D | Option | Level V evidence: little or no systematic empirical evidence |
