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.
Method of categorizing level of evidence available for each topic.
| Category of Evidence | Evidence Available |
|---|---|
| 1A | From metaanalysis of randomized controlled trials. |
| 1B | From at least 1 randomized controlled trial. |
| 2A | From at least 1 controlled study without randomization. |
| 2B | From at least 1 quasi-experimental study. |
| 3 | From descriptive studies, such as comparative studies, correlation studies, or case-control studies. |
| 4 | From expert committee reports or opinions and/or clinical experience of respected authorities. |