Table 7:
Bias ratings of prospective cohort studies, via Newcastle-Ottawa scores
| File name | Representativeness of the exposed cohort | Selection of nonexposed cohort | Ascertainment of exposure | that outcome of interest was not present at the start of the study | Comparability | Assessment of outcome | Length of follow-up | Adequacy of follow-up | Bias rating | Bias reasoning |
|---|---|---|---|---|---|---|---|---|---|---|
| De Geest (1998)25 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 7 out of 9 | No controls/adjustment |
| De Geest (2014)16 | 1 | 1 | 1 | 1 | 2 | 0 | 1 | 0 | 7 out of 9 | Self-reported outcomes High attrition rate |
| Dobbels (2004)17 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 out of 9 | N/A |
| Doesch (2013)18 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 6 out of 9 | No controls/adjustment Self-reported outcomes |
| Doesch (2010)19 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 6 out of 9 | No controls/adjustment Self-reported outcomes |
| Gomis-Pastor (2020)21 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 6 out of 9 | No controls/adjustment Self-reported outcomes |
| Grady (1998)29 | 1 | 1 | 1 | 1 | 2 | 0 | 1 | 0 | 7 out of 9 | Self-reported outcomes High attrition rate |
| Farmer (2013)27 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 out of 9 | N/A |
| Vitinius (2019)24 | 1 | 1 | 1 | 1 | 2 | 0 | 1 | 1 | 8 out of 9 | Self-reported outcomes |
N/A: not applicable