| (Aljefree & Ahmed, 2015) [26] | (Alharbi et al., 2014) [21] | (Alhyas et al., 2012) [24] | Musaiger and Al-Hazzaa 2012 [23] | Alhyas et al., 2011) [25] | (S. W. Ng et al., 2011) [28] | (Musaiger, 2011) [22] | (Akl et al., 2011) [58] | (Mabry et al., 2010a) [38] | (Mabry et al., 2010b) [66] | (Motlagh et al., 2009) [27] |
---|---|---|---|---|---|---|---|---|---|---|---|
1. Was an ‘a priori’ design provided? | No | No | Yes | Yes | Yes | No | No | Yes | No | No | Yes |
2. Was there duplicate study selection and data extraction? | Yes | Yes | Yes | No | Yes | No | No | Yes | Can’t answer | No | No |
3. Was a comprehensive literature search performed? | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | No |
4. Was the status of publication (i.e. grey literature) used as an inclusion criterion? | No | No | Yes | No | No | Yes | No | No | No | No | No |
5. Was a list of studies (included and excluded) provided? | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | No |
6. Were the characteristics of the included studies provided? | Yes | Yes | Yes | No | Yes | Yes | No | Yes | Yes | Yes | Yes |
7. Was the scientific quality of the included studies assessed and documented? | Yes | No | Yes | No | Yes | No | No | Yes | Yes | Yes | No |
8. Was the scientific quality of the included studies used appropriately in formulating conclusions? | No | No | Yes | No | Yes | No | No | Yes | No | Yes | Yes |
9. Were the methods used to combine the findings of studies appropriate? | No | No | No | n/a | n/a | n/a | n/a | n/a | n/a | n/a | Yes |
10. Was the likelihood of publication bias assessed? | No | No | No | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a |
11. Was the conflict of interest included? | Yes | Yes | Yes | No | Yes | Yes | No | Yes | Yes | Yes | Yes |
Total/11 | 6 | 4 | 9 | 3 | 8 | 5 | 2 | 7 | 5 | 5 | 5 |