From: Evidence-based practice in Behçet’s disease: identifying areas of unmet need for 2014
Level of evidence | Description | Categorisation in this analysis |
---|---|---|
1++ | High quality meta-analyses, systematic reviews of RCTs, or RCTs with a very low risk of bias | 1 |
1+ | Well conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias | |
1- | Meta-analyses, systematic reviews or RCTs, or RCTs with a high risk of bias | |
2++ | High quality systematic reviews of case-control or cohort studies or High quality case-control or cohort studies with a very low risk of confounding, bias, or chance and a high probability that the relationship is causal | 2 |
2+ | Well conducted case-control or cohort studies with a low risk of confounding, bias, or chance and a moderate probability that the relationship is causal | |
2- | Case-control or cohort studies with a high risk of confounding, bias, or chance and a significant risk that the relationship is not causal | |
3 | Non-analytic studies, e.g. case reports, case series | 3 |
4 | Expert opinion | 4 |