Table 2.
The Newcastle-Ottawa Scale (NOS) for assessing the quality of cohort studies.
| First author | Sakata | Jee | Chien | Bos | Gerber | Hozawa | Strasak1 | Strasak2 | Holme | Storhaug | Zhang | Shi | Tu | Chaudhary | Li | Norvik | Chen | Koton | Lehto |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Year | 2001 | 2004 | 2005 | 2006 | 2006 | 2006 | 2008 | 2008 | 2009 | 2013 | 2016 | 2017 | 2019 | 2020 | 2020 | 2017 | 2011 | 2008 | 1998 |
| 1. Representativeness of the exposed cohort | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 1 |
| 2. Selection of the non-exposed cohort | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 3. Ascertainment of exposure | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 4. Demonstration that outcome of interest was not present at start study | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 5. Control for important cohort | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 6. Additional factors | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 |
| 7. Assessment of outcome | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 |
| 8. Follow up | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 1 | 1 |
| 9. Adequacy of follow up of cohorts | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 |
| Score | 9 | 7 | 7 | 6 | 6 | 8 | 9 | 9 | 7 | 7 | 7 | 6 | 6 | 8 | 7 | 7 | 5 | 7 | 7 |