Table 2.
Quality Assessment of 28 Included Studies Using the Newcastle-Ottawa Scale15
| Stars From Newcastle-Ottawa Scale, No.a | |||
|---|---|---|---|
| Source | Selection | Comparability | Outcome |
| Cohort studies | |||
| Brown et al,17 2006 | 2 | 0 | 2 |
| Srinivasan et al,18 2010 | 4 | 2 | 3 |
| Goh et al,19 2013 | 3 | 2 | 3 |
| Carroll et al,20 2006 | 3 | 2 | 3 |
| Yu et al,21 2011 | 2 | 1 | 3 |
| Lange et al,22 2005 | 3 | 2 | 2 |
| Baillargeon et al,23 2006 | 2 | 2 | 3 |
| Barker et al,24 2011 | 3 | 2 | 3 |
| Hingorani et al,25 2011 | 3 | 0 | 3 |
| Rana et al,26 2009 | 2 | 0 | 3 |
| Patel et al,27 2010 | 3 | 2 | 3 |
| Garey et al,28 2010 | 2 | 0 | 2 |
| Hanevold et al,29 2005 | 3 | 2 | 3 |
| Kaufman et al,30 2009 | 3 | 2 | 3 |
| Dick et al,31 2010 | 3 | 2 | 3 |
| Rossano et al,32 2007 | 1 | 2 | 2 |
| Kaufman et al,33 2008 | 1 | 2 | 3 |
| Nafiu et al,34 2009 | 3 | 0 | 3 |
| Hijiya et al,35 2006 | 3 | 2 | 3 |
| Bulley et al,36 2008 | 2 | 2 | 2 |
| Fernandez et al,37 2009 | 3 | 2 | 3 |
| Pine et al,38 2011 | 3 | 2 | 3 |
| Kraft et al,39 2012 | 3 | 0 | 2 |
| White et al,40 2012 | 3 | 2 | 2 |
| Case-control studies | |||
| Morgan et al,41 2010 | 3 | 1 | 0 |
| Butturini et al,42 2007 | 3 | 2 | 3 |
| Linam et al,43 2009 | 3 | 2 | 2 |
| Fung et al,44 2010 | 2 | 2 | 3 |
a
Higher quality studies are reflected by higher numbers of stars in each category. The maximum possible star scores for each study criteria are 4 for selection, 2 for comparability, and 3 for outcome or exposure, for a total possible score of 9.