Table 1 Evidence level of systematic reviews
From: Public health interventions in midwifery: a systematic review of systematic reviews
Score | Source of evidence |
|---|---|
1++ | High quality meta analyses or systematic reviews of RCT’s |
1+ | Well conducted meta analyses or systematic reviews of RCT’s |
1- | Meta analyses or systematic reviews of RCT’s |
2++ | High quality systematic reviews of case control or cohort studies |
2+ | Well conducted case control or cohort studies with low risk of bias |
2- | Case control or cohort studies with high risk of bias |
3 | Case reports or case series |
4 | Expert opinion or formal consensus |