Table 2. Assessment of Methodological Quality of Included Studies.

	Randomizationa	Similar atbaselineb	Criteriaspecifiedc	Assessorblindedd	Allocationconcealmente	Variabilityoutcomef	ITAg	Totalscore
Burling (1992)[67]	Unknown	YES	YES	Unknown	YES	YES	YES	5
Marcus (1995)[55]	YES	YES	YES	Unknown	Unknown	YES	YES	5
Donaghy (1997)[26]	YES	YES	YES	Unknown	Unknown	YES	YES	5
Martin (1997)[68]	YES	YES	YES	Unknown	YES	YES	NO	5
Marcus (1999)[56]	YES	YES	YES	YES	Unknown	YES	YES	6
Huang (2000a)[52]	YES	YES	YES	YES	Unknown	YES	NO	5
Huang (2000b)[53]	YES	YES	YES	YES	Unknown	YES	YES	6
Li (2002) [51]	YES	YES	YES	Unknown	Unknown	YES	YES	5
Ussher (2003)[57]	YES	YES	YES	Unknown	Unknown	YES	YES	5
Marcus (2005)[58]	YES	YES	YES	Unknown	Unknown	YES	YES	5
Char (2006)[65]	YES	YES	YES	YES	Unknown	YES	YES	6
Sareen (2007) [66]	YES	YES	YES	NO	Unknown	YES	YES	5
Prapavessis (2007)[59]	YES	YES	YES	YES	Unknown	YES	YES	6
Ussher (2007)[60]	YES	YES	YES	YES	YES	YES	YES	7
Kinnunen (2008)[61]	YES	YES	YES	Unknown	YES	YES	NO	5
Vickers (2009)[27]	YES	YES	YES	Unknown	YES	YES	NO	5
Williams (2010)[62]	YES	YES	YES	Unknown	Unknown	YES	NO	4
Bock (2012)[63]	YES	YES	YES	Unknown	Unknown	YES	YES	5
Whiteley (2012)[64]	YES	YES	YES	Unknown	YES	YES	YES	6
Li (2013)[54]	YES	YES	YES	Unknown	YES	YES	NO	5
Smelson (2013)[69]	YES	YES	YES	Unknown	Unknown	YES	NO	4
Zhuang (2013)[39]	YES	YES	YES	Unknown	YES	YES	NO	5

^aWas randomization performed?

^bWere the groups similar at baseline regarding important prognostic indicators?

^cWere the eligibility criteria specified?

^dWas the outcome assessor blinded?

^eWas allocation concealment adequate?

^fWere point estimates and measures of variability presented for the primary outcome measures?

^gDid the analysis include an intention to treat analysis?