Table 4.

Cochrane risk of bias tool for randomized controlled trials

Selected studies	Adequate sequence generation	Allocation concealment	Selective reporting	Blinding of participants and personnel	Blinding of outcome assessment	Incomplete outcome data	Other bias	AHRQ score
Thorp et al., 1978[12]	Unclear	Unclear	Yes	No	No	No	Unclear	Poor
Ellinger et al., 1979[13]	Unclear	Yes	Unclear	Yes	Unclear	Unclear	Unclear	Poor
Nascimento et al., 2004[14]	Yes	Yes	No	Yes	Yes	Yes	Unclear	Fair
Kawai et al., 2005[8]	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Good
Heydecke et al., 2007[15]	Yes	Yes	Yes	Yes	Yes	Yes	Unclear	Fair
Heydecke et al., 2008[16]	Yes	Yes	Yes	Yes	Yes	Yes	Unclear	Fair
Vivell et al., 2009[17]	Yes	Yes	Unclear	Unclear	Yes	Unclear	Unclear	Poor
Kumar and D’souza 2010[18]	Unclear	Yes	Yes	Unclear	Yes	Yes	Unclear	Poor
Kawai et al., 2010[19]	Yes	Yes	Yes	Unclear	Yes	Yes	Unclear	Fair
Cunha et al., 2013[20]	Yes	Yes	Yes	Yes	Yes	Yes	Unclear	Fair
Omar et al., 2013[21]	Yes	Yes	Yes	Yes	Yes	Yes	Unclear	Fair
Vecchia et al., 2014[22]	Yes	Yes	Yes	Unclear	Yes	Yes	Unclear	Poor
von Stein-Lausnitz et al., 2017[23]	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Good
von Stein-Lausnitz et al., 2018[24]	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Good
Ahlers et al., 2018[25]	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Good

AHRQ: Agency for Healthcare Research and Quality