Table 2 The Newcastle-Ottawa scale (NOS) for assessing the methodology quality of cohort studies
Study | Selection | Comparability | Outcome | Scorea | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Representativeness of the exposed cohort | Selection of control | Ascertainment of exposure | Demonstration that outcome of interest was not present at start of study | Comparability of cohorts on the basis of the design or analysis | Assessment of outcome | Was followed up long enough for outcomes to occur | Adequacy of follow-up of cohorts | Number of loss/n | ||
HÃ¥konsen 2012 [29] | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 2906/5716 | 8 |
Ernst 2012 [30] | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | Not mentioned | 8 |
Windham 2008 [31] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | Not mentioned | 6 |
Ferris 2010 [32] | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 466/841 | 8 |
Behie 2015 [34] | 1 | 1 | 1 | 1 | 2 | 1 | 0 | 0 | 953/2446 | 7 |
Windham 2004 [35] | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9/1003 | 9 |
Tehrani 2014 [36] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | Not mentioned | 6 |
Rubin 2009 [37] | 1 | 1 | 1 | 1 | 2 | 1 | 0 | 1 | 413/2940 | 8 |
Shrestha 2011 [23] | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 2248/5427 | 8 |
Maisonet 2010 [38] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1104/5842 | 7 |
Fried 2001 [39] | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 38/190 | 6 |
Wang 2012 [40] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 281/856 | 6 |
Flom 2017 [41] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 180/1314 | 7 |
Dossus 2012 [42] | 1 | 1 | 1 | 0 | 2 | 1 | 1 | 1 | NAb | 8 |
Hart 2009 [43] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1068/2868 | 6 |
Morris 2010 [44] | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | NA | 7 |
D’Aloisio 2013 [45] | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | NA | 7 |
Ravnborg 2011 [46] | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | NA | 6 |
Carter 2014 [47] | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0/265 | 6 |
Liu 2010 [48] | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 16/810 | 7 |