Table 4 Methodological quality of included studies using the AMSTAR checklist
CRITERIA | Cole-Lewis 2010 [ 19 ] | De Jongh 2012 [ 18 ] | Finitsis 2014 [ 20 ] | Gurol-Urganci 2012 [ 22 ] | Gurol-Urganci 2013 [ 21 ] | Horvath 2012 [ 6 ] | Militello 2012 [ 23 ] | Nglazi 2013 [ 24 ] | Vodopivec-Jamsek 2012 [ 25 ] |
|---|---|---|---|---|---|---|---|---|---|
Was an 'a priori' design provided? | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 |
Was there duplicate study selection and data extraction? | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Was a comprehensive literature search performed? | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Was the status of publication (i.e. grey literature) used as an inclusion criterion? | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
Was a list of studies (included and excluded) provided? | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
Were the characteristics of the included studies provided? | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Was the scientific quality of the included studies assessed and documented? | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Was the scientific quality of the included studies used appropriately in formulating conclusions? | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Were the methods used to combine the findings of studies appropriate? | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Was the likelihood of publication bias assessed? | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 0 |
Was the conflict of interest included? | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
AMSTAR scores | 5 | 9 | 8 | 10 | 10 | 10 | 7 | 9 | 9 |
Ranking | Medium | High | High | High | High | High | Medium | High | High |