Grades of recommendations
| Grade | Type of evidence |
| A | At least one meta-analysis, systematic review or randomised controlled trial (RCT) rated as 1++ and directly applicable to the target population; or A systematic review of RCTs or a body of evidence consisting principally of studies rated as 1+ directly applicable to the target population and demonstrating overall consistency of results |
| B | A body of evidence including studies rated as 2++ directly applicable to the target population and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 1++ or 1+ |
| C | A body of evidence including studies rated as 2+ directly applicable to the target population and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 2++ |
| D | Evidence level 3or 4; or Extrapolated evidence from studies rated as 2+ |
| ✓ | Important practical points for which there is no—nor is there likely to be any—research evidence. The guideline committee wishes to emphasise these as Good Practice Points (GPP) |