Quality assessment
A quality assessment of the studies was performed by two independent
reviewers (E.B and T.P) using the Cochrane Collaboration risk of bias
tool7. Any disagreement was resolved by discussion or
by consulting a third investigator (J.S and /or C.D). We recorded the
methods used to generate the randomisation schedule and conceal
treatment allocation as well as find out whether blinding was
implemented for participants, personnel and outcomes assessment and if
there was evidence of incomplete outcomes data and selective reporting
of outcomes.