| |
Selection bias
|
Confounding bias
|
Outcome measurement bias
|
|---|
|
Bruno (2007) [34]
|
Low
|
Moderate
|
Low
|
|
Giron-Gonzalez (2007) [29]
|
Unclear
|
Moderate
|
Low
|
|
Limketkai (2012) [23]
|
Low
|
Low
|
Low
|
|
Macias (2006) [25]
|
Low
|
Moderate
|
Low
|
|
Macias (2009) [24]
|
Low
|
Low
|
Unclear
|
|
Mariné-Barjoan (2004) [35]
|
Low
|
High
|
Low
|
|
Mehta (2005) [30]
|
Unclear
|
High
|
High
|
|
Merchante (2006) [31]
|
Unclear
|
High
|
Low
|
|
Pineda (2009) [32]
|
Low
|
Moderate
|
Low
|
|
Qurishi (2003) [26]
|
Unclear
|
Low
|
Low
|
|
Ragni (2009) [27]
|
Low
|
Low
|
Unclear
|
|
Reiberger (2010) [36]
|
Low
|
High
|
Low
|
|
Sanmartin (2014) [33]
|
Low
|
High
|
High
|
|
Schiavini (2006) [28]
|
Unclear
|
High
|
Low
|
|
Total risk of bias
|
9 low
|
4 low
|
10 low
|
|
0 high
|
6 high
|
2 high
|
|
5 unclear
|
4 moderate
|
2 unclear
|
