Table 3.

Evaluation of risk of bias in the 22 included studies based on the seven items in the Cochrane Risk of Bias (RoB) tool

study	random sequence generation	allocation concealment	blinding of participants and providers	blinding of outcome assessment	incomplete outcome data	selective reporting	other biasesa	overall risk of biasb
Chanpatana 1999[11]	Unclear	Low	Unclear	Low	Low	Unclear	Unclear	Unclear
Goswami 2003[17]	Low	Low	Low	Low	Low	Unclear	Unclear	Unclear
Yang 2005[27]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Ding 2007[13]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Cai 2008[10]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Braga 2009[9]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Jiang 2009[18]	Low	Unclear	Unclear	Unclear	Low	Unclear	Unclear	Unclear
Zhou 2009[31]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Liu 2010a[21]	Unclear	Unclear	Unclear	Unclear	Low	Unclear	Unclear	Unclear
Liu 2010b[22]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Ding 2011[14]	Unclear	Unclear	Unclear	Unclear	Low	Unclear	Unclear	Unclear
Du 2011[15]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Duo 2011[16]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Jiang 2011[19]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Yang 2011[28]	Unclear	Unclear	Unclear	Unclear	Low	Unclear	Unclear	Unclear
Chen 2012[29]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Wang 2012[32]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Zhang 2012[30]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Chen 2013[12	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Jiang 2013[20]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Wang 2013[26]	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Petrides 2015[23]	Unclear	Unclear	High	Low	Low	Unclear	Unclear	High
kappac	1.00	1.00	0.49	0.82	1.00	1.00	1.00	0.75

^a Other biases considered include including study-specific biases or concerns about fraudulent results

^b If any of seven items are coded high-risk of bias the overall study is classified as high-risk, if all seven items are coded as low-risk the overall study is classified as low-risk; all other studies (i.e., those with some items coded ‘unclear’ and no items coded as high-risk) are classified as ‘unclear’

^c Weighted kappa values for inter-rater reliability of the two independent coders who assessed each item for the 23 studies