Table 3.

Quality Assessment of Included Trials

Study, Year, Country	Random- ization Adequate	Primary Outcome Defined	Dropouts Described	Point Estimates/ Measures of Variability	Intention- to-Treat	Power Calculation Described	Double- Blinding	Eligibility Criteria Predefined
O’Brien et al,⁹ 1993, USA	Yes	Unclear	Yes	Yes	No	No	Yes	Yes
Marvez-Valls et al,⁷ 1998, USA	Yes	Yes	Yes (no drop-outs)	Yes	No	Yes	Yes	Yes
Wei et al, 2002,⁸ USA	Unclear	Unclear	Yes	Yes	No	No	Yes	Yes
Kidermann et al,⁶ 2005, Israel	Yes	Yes	Yes (no drop-outs)	Yes	No	Yes	Yes	Yes
Tasar et al,¹⁰ 2008, Turkey	Yes	No	Yes (no drop-outs)	Yes	No	No	Yes	Yes
Bulloch et al,¹¹ 2003, USA	Yes	No	Yes	Yes	No	Yes	Yes	Yes
Olympia et al,¹² 2005, USA	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes
Niland et al,¹³ 2006, USA	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes