Table 2.
Quality assessment with the Newcastle-Ottawa Scale
| Selection | Comparability | Outcome | |||||||
| Author | Representativeness of the exposed cohort | Selection of the non-exposed cohort | 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 follow-up long enough for outcomes to occur | Adequacy of follow up of cohorts | Total |
| Fumery M et al7 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Chaparro M et al19 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Dalal RS et al20,24,25 | ★ | NA | ★ | ★ | NA | ★ | ★ | 5 | |
| Amiot A et al8 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Ochsenkühn T et al21 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Chiappetta MF et al22 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Hong S et al23 | ★ | NA | ★ | ★ | NA | ★ | ★ | 5 | |
| Haraikawa M et al26 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Yamana Y et al27 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Asaeda K et al28 | ★ | NA | ★ | ★ | NA | ★ | ★ | 5 | |
| Ando K et al29 | ★ | NA | ★ | ★ | NA | ★ | ★ | ★ | 6 |
| Dominik E et al30 | ★ | NA | ★ | ★ | NA | ★ | ★ | 5 | |
NA: not applicable