Table 3

Cochrane tool to assess risk of bias for randomised controlled trials

Vahidi et al 32 Aurilio et al 36 Aurilio et al 28 Mitchell and Fallon33 Persson et al 34
Random sequence generation (selection bias) + + ? + +
Allocation concealment (selection bias) + + ? + +
Blinding (performance bias and detection bias)
All outcomes		 + − − + +
Incomplete outcome data (attrition bias)
All outcomes		 + + + − +
Selective reporting (reporting bias) + + + + +
Other bias + + + + −