Grading of recommendations
| Grade | Details |
|---|---|
| A | The recommended action is supported by good evidence based on well designed studies (level of evidence I or II) directly applicable to the target |
| B | The recommendation is supported by fair evidence based on well designed studies (level of evidence I, II, or III-1) from which evidence can be extrapolated to the target population |
| or | |
| The evidence is supported by weaker studies (level III or IV evidence) with overall consistency of results and directly relevant to the target population | |
| C | The recommendation is supported by expert opinion only, based either on weaker studies (level III-2, III-3, or IV evidence) from which evidence can be extrapolated to the target population, or consensus of expert opinion |