Table 1.

Methodological quality of included studies

Study Authors, date	Randomization/allocation concealment	Blinding of patients/outcomes assessment	Prior estimate of sample size	Withdrawals per group reported	ITT analysis adequate	Report of measures of precision	Data inconsistencies	Funding reported
Kanowski et al. 1996/2003 [29,36]	Yes/yes	Yes/yes	Partlya	Partlyb	Yes	Yes	No	No
Le Bars et al. 1997/2000 [30,37]	Yes/yes	Yes/unclear	Yes	Yes	Yes	Yes	No	Yes
Maurer et al. 1997 [31]	Yes/unclear	Yes/unclear	No	Yes	No	No	No	No
van Dongen et al. 2000 [34,45]	Yes/yes	Yes/yes	Yes	Yes	No	Yes	Yesc	Yes
Schneider et al. 2005 [33]	Yes/yes	Yes/yes	Yes	Yes	Yes	Yes	No	Yes
Yancheva et al 2009 [35]	Yes/unclear	Yes/unclear	No	Yes	Yes	Yes	Yes	Yes
Napryeyenko et al. 2007 [32]	Yes/unclear	Yes/unclear	Yes	Yes	Yes	Yes	No	Yes
McCarney et al. 2008 [2]	Yes/yes	Yes/yes	Partlya	Yes	Yes	Yes	No	Yes
Ihl et al. 2009	Yes/yes	Yes/yes	No	Yes	Yes	Yes	No	Yes

a: Less patients were included than planned; b: Drop-out rates were reported, but without reference to study arm; c: Multiple re-randomization schemes.

ITT = Intent-to-treat analysis.