Table 2

Author (ref)	Random Sequence Generation	Allocation Concealment	Blinding of Participants and Personnel	Blinding of Outcome Assessment	Incomplete Outcome Data	Selective Reporting
Jacobsen 2002 (12)*	Low1	Low1	Unclear3	Low6	Low7	Unclear9
Jacobsen 2003 (13)*	Low	Low	Unclear	Low	Low	Unclear
Jacobsen 2003 (14)*	Low	Low	Unclear	Low	Low	Unclear
Mehdi 2009 (15)*	Unclear2	Low	Low4	Low	Low	Unclear
Parving 2008 (16)*	Low	Low	Low	Low	Low	Unclear
Rossing 2002 (17)*	Low	Low	Low	Low	Low	Unclear
Rossing 2003 (18)*	Low	Low	Low	Low	Low	Unlcear
Rossing 2005 (19)*	Low	Low	Low	Low	Low	Unclear
Schjoedt 2005 (20)*	Low	Low	Low	Low	Low	Unclear
Schjoedt 2006 (21)*	Low	Low	Low	Low	Low	Unclear
Song 2003 (22)*	Unclear	Unclear2	Unclear	Low	Low	Unclear
Tan 2010 (23)*	Unclear	Unclear	High5	Low	Low	Unclear
Cetinkaya 2004 (24)	Unclear	Unclear	High	Low	Unclear8	High10
Kim 2003 (25)	Unclear	Unclear	Unclear	Low	Low	High
Matos 2005 (26)	Low	Unclear	High	Low	Low	High
Song 2006 (27)	Low	Unclear	High	Low	Low	High

*Included in analysis for primary outcome; 1Method stated and appropriate; 2Method not stated; 3Characteristic of placebo not stated; 4Matching placebo; 5No placebo control; 6Not likely to be influenced by lack of blinding, even if present; 7Dropouts accounted for appropriately; 8Unclear if dropouts occurred; 9Insufficient information to judge; 10Primary outcome unable to be included in meta-analysis

Table 2: Risk of Bias in Included Studies Based on Cochrane Assessment Tool.