Strength of recommendation
| Category | Directly based on: |
|---|---|
| A | Category 1 evidence |
| B | Category 2 evidence or extrapolated recommendation from category 1 evidence |
| C | Category 3 evidence or extrapolated recommendation from category 1 or 2 evidence |
| D | Category 4 evidence or extrapolated recommendation from category 2 or 3 evidence |