Table 1 Summary of methodological quality assessment scores
Author and publication year (possible score) | Reporting (11) | External validity (3) | Internal validity—bias (7) | Internal validity—confounding (6) | Power (5) | Total (32) |
|---|---|---|---|---|---|---|
Alexander et al., 2001 [9] | 11 | 3 | 5 | 3 | 1 | 23 |
Clemson et al., 2012 [13] | 10 | 2 | 6 | 5 | 1 | 24 |
Cress et al., 1996 [46] | 8 | 1 | 5 | 3 | 0 | 17 |
de Vreede et al., 2005 [35] | 11 | 2 | 6 | 3 | 1 | 23 |
Dobek et al., 2006 [17] | 9 | 0 | 4 | 1 | 1 | 15 |
Gillies et al., 1999 [7] | 10 | 1 | 4 | 3 | 0 | 18 |
Giné-Garriga et al., 2010 [51] | 11 | 2 | 5 | 5 | 1 | 24 |
Helbostad et al., 2004 [8] | 11 | 0 | 6 | 6 | 1 | 24 |
Krebs et al., 2007 [18] | 11 | 2 | 7 | 5 | 0 | 25 |
Littbrand et al., 2009 [1] | 11 | 3 | 7 | 6 | 1 | 28 |
Manini et al., 2007 [12] | 11 | 1 | 4 | 5 | 1 | 22 |
Skelton et al., 1996 [31] | 10 | 2 | 5 | 4 | 1 | 22 |
Whitehurst et al., 2005 [38] | 8 | 2 | 5 | 2 | 1 | 18 |