Table 2.

Summary of methodological quality

Parameters	Baker et al.(19)	Ennis et al.(24)	Petrofsky et al.(23)	Lundeberg et al.(20)	Peters et al.(21)	Petrofsky et al.(22)	Minatel et al.(25)	Kaviani et al.(26)
Randomised	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Randomisation appropriate	Not described	Yes	Not described	Yes	Yes	Not described	Not described	Yes
Blinding	Yes	Yes	No	Yes	Yes	No	Yes	Yes
Blinding procedure	Not described	Double‐blinded	Not described	Double‐blinded	Double‐blinded	Not described	Double‐blinded	Double‐blinded
Withdrawals and dropouts	No	Yes	No	Yes	Yes	No	No	Yes
Inclusion or exclusion criteria	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Adverse events reported	No	Yes	No	No	No	No	Yes	Yes
Method of statistical analysis	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Sample size calculation	No	No	No	No	No	No	No	No
Allocation concealment	No	No	No	No	No	No	No	No
Intention to treat analysis	No	Yes	No	Yes	No	No	No	No