Table 2 Newcastle–Ottawa Scale for quality assessment of studies included in this meta-analysis
References | Representativeness of sample | Size sample | Source of information | Demonstration that outcome was not present at study start | Confusion variable control | Assessment of outcome | Enough follow-up period | Newcastle–Ottawa scale score |
|---|---|---|---|---|---|---|---|---|
Wakhloo et al. [10] | ★ | ★ | ★ | ★ | ★ | ★ | 6/7 | |
Taschner et al. [11] | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7/7 |
Mahajan et al. [12] | ★ | ★ | ★ | ★ | ★ | 5/7 | ||
Meyers et al. [13] | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7/7 |
Orru et al. [14] | ★ | ★ | ★ | ★ | ★ | ★ | 6/7 |