Table 3 Quality assessment scores
Reference | Reporting (max = 11) | External validity (max = 3) | Internal validity | Power (max = 5) | Total (max = 32) | |
|---|---|---|---|---|---|---|
| Â | Â | Â | Bias (max = 7) | Confounding (max = 6) | Â | Â |
Allam, 2006 [21] | 9 | 0 | 4 | 2 | 3 | 18 |
Batista et al., 2011 [26] | 5 | 0 | 2 | 2 | 0 | 9 |
Colen et al., 2013 [27] | 9 | 2 | 5 | 2 | 3 | 21 |
Dayer et al., 2009 [28] | 10 | 0 | 3 | 2 | 0 | 15 |
Hamilton et al., 2005 [29] | 9 | 2 | 2 | 3 | 0 | 16 |
Kim et al., 2012 [22] | 9 | 0 | 4 | 2 | 3 | 18 |
Laborde, 2005 [30] | 9 | 2 | 2 | 2 | 0 | 15 |
Laborde, 2009 [31] | 8 | 2 | 2 | 2 | 0 | 14 |
La Fontaine et al., 2008 [32] | 9 | 3 | 4 | 3 | 5 | 24 |
Lin et al., 1996 [33] | 8 | 0 | 3 | 1 | 0 | 12 |
Mueller et al., 2003 [15] | 11 | 0 | 5 | 6 | 5 | 27 |