Supplementary Table 3.

Assessing risk of bias: Randomised controlled trials

Item	Wyrsch et al
Random sequence generation	High risk
Allocation concealment	High risk
Blinding of participants and personnel	High risk
Blinding of outcome assessment	High risk
Incomplete outcome data	Unclear
Selective reporting	Low risk
Other sources of bias *	High risk
Risk of bias	High

* Other sources of bias: Important concerns about surgical randomization