Level of evidence and grading of therapeutic recommendations, according to criteria endorsed by EULAR/EUVAS6,24. From Dougados, et al. Ann Rheum Dis 2004;63:1172–6; with permission.
Strength of recommendation.
| Strength of Recommendation | Directly Based on Level of Evidence |
|---|---|
| A | Category 1 evidence |
| B | Category 2 evidence or extrapolated recommendations from category 1 evidence. |
| C | Category 3 evidence or extrapolated recommendations from category 1 or 2 evidence. |
| D | Category 4 evidence or extrapolated recommendations from category 2 or 3 evidence. |
EULAR: European League Against Rheumatism; EUVAS: European Vasculitis Society.