Table 1 Level of evidence
From: Bariatric emergencies: current evidence and strategies of management
Levels of Evidence (Scottish Intercollegiate Guidelines Network, SIGN) | |
|---|---|
1++ | High quality meta-analyses, systematic reviews of RCTs, or RCTs with a very low risk of bias |
1+ | Well conducted meta-analyses, systematic reviews, or RCTs with a low risk of bias |
1- | Meta-analyses, systematic reviews, or RCTs with a high risk of bias |
2++ | High quality systematic reviews of case control or cohort studies |
| Â | High quality case control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal |
2+ | Well conducted case control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal |
2- | Case control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is not causal |
3 | Non-analytic studies, eg case reports, case series |
4 | Expert opinion |