TABLE 3.
Assessment of 9 cohort studies by Newcastle‐Ottawa Scale
| Parameter | Hummel et al.30 (2009) | Fleiner et al.31 (2012) | Konstantinisis et al.32 (2013) | Poletti et al.40 (2016) | Fornazieri et al.41 (2019) | Pellegrino et al.36 (2019) | Bratt et al.42 (2020) | Yan et al.33 (2018) | Jung et al.43 (2019) |
|---|---|---|---|---|---|---|---|---|---|
| Representativeness of the exposed cohort | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 |
| Selection of the non‐exposed cohort | 1 | 1 | 1 | 1 | 1 | 1 | – | – | – |
| Ascertainment of exposure | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 0 |
| Demonstration that outcome of interest was not present at start of study | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Comparability of cohorts on the basis of the design or analysis | 2 | 0 | 2 | 1 | 0 | 1 | – | – | – |
| Assessment of outcome | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Was follow‐up long enough for outcomes to occur | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Adequacy of follow‐up of cohorts | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 |
| Total score | 8 | 7 | 8 | 7 | 6 | 6 | 5 | 6 | 5 |