Table 2.
Risk of bias for included studies.
| Study ID | Random Sequence Generation | Allocation Concealment | Blinding | Attrition Bias | Selective Outcome Reporting |
|---|---|---|---|---|---|
| Prakash 2016 | U | U | U | U | L |
| Farzaneh 2014 | U | U | L | H | L |
| Rathi 2013 | U | U | U | H | L |
| Devra 2012 | U | U | U | U | L |
| Huseini 2012 | L | L | L | L | L |
| Joseph 2012 | U | U | U | U | L |
| Sabzghabaee 2012 | U | L | U | U | L |
| Sharma 2012 | U | U | L | H | L |
| Sobenin 2010 | U | U | L | H | L |
| Nohr 2009 | L | L | L | H | L |
| Qidwai 2009 | U | U | L | H | L |
| Alizadeh-Navaei 2008 | U | U | L | U | L |
| Sobenin 2008 | U | U | L | U | L |
| Gardner 2007 | L | L | L | L | L |
| Ashraf 2005 | U | U | H | L | L |
| Tanamai 2004 | U | U | L | H | L |
| Satitvipawee 2003 | L | L | L | L | L |
| Szapary 2003 | L | L | L | L | L |
| Venkataramaiah 2002 | U | U | U | U | U |
| Kannar 2001 | U | U | L | L | L |
| Gardner 2001 | U | U | L | L | L |
| Adler 1997 | U | U | L | L | L |
| Awasthi 1997 | U | U | L | H | L |
| Gaur 1997 | U | U | U | H | L |
| Singh 1994 | U | U | L | H | L |
| Jain 1993 | U | U | H | L | L |
| Tiwari 1991 | U | U | L | H | L |
| Mader 1990 | L | L | L | L | L |
| Nityanand 1989 | U | U | L | H | L |
| Verma 1988 | U | U | L | U | L |
| Kotiyal 1984 | U | U | L | U | L |
| Kuppurajan 1978 | U | U | L | H | L |
L: low risk; H: high risk; U: unclear risk.