Table 2.
Quality assessment by the Newcastle-Ottawa Scale
| Study | Study design | Selection | Comparability | Outcome | Total |
|---|---|---|---|---|---|
| 1) Rodriguez A (2008) | Cohort | **** | * | *** | 8 |
| 2) Rodriguez A (2010) | Cohort | **** | * | *** | 8 |
| 3) Brion MJ (2011) | Cohort | *** | * | *** | 7 |
| 4) Buss C (2012) | Cohort | *** | - | *** | 6 |
| 5) Hinkle SN (2013) | Cohort | *** | ** | ** | 7 |
| 6) Chen Q (2014) | Cohort | **** | ** | *** | 9 |
| 7) Van Mil (2014) | Cohort | *** | ** | ** | 7 |
| 8) Jo H (2015) | Cohort | *** | * | ** | 6 |
| 9) Andersen CH (2017) | Cohort | **** | * | *** | 8 |
| 10) Musser ED (2017) | Cohort | **** | ** | *** | 9 |
| 11) Casas M (2017) | Cohort | *** | ** | *** | 8 |
| 12) Daraki V (2017) | Cohort | *** | * | *** | 7 |
| 13) Mina TH (2017) | Cohort | **** | * | *** | 8 |
| 14) Mikkelsen SH (2017) | Cohort | **** | ** | *** | 9 |