Table 2 Priori scores for each critical appraisal tool

RoB 2 tool for RCTs

Low risk of bias: judgement of low risk for all domains

Moderate risk of bias: judgement of some concerns in 1 or 2 domains

High risk of bias: judgement of high risk in 1 or more domain OR judgement of some concerns for 3 or more domains

Newcastle Ottawa Scale for cohort studies

Low risk of bias: 8–9 points

Moderate risk of bias: 6–7 points

High risk of bias: 5 or less points

Newcastle Ottawa Scale for case–control studies

Low risk of bias: 8–9 points

Moderate risk of bias: 6–7 points

High risk of bias: 5 or less points

JBI checklist for cross-sectional studies

Low risk of bias: 7–8 questions met

Moderate risk of bias: 4–6 questions met

High risk of bias: 3 or less questions met

JBI checklist for case series

Low risk of bias: 8–10 questions met

Moderate risk of bias: 5–7 questions met

High risk of bias: 4 or less questions met