Table 2. The assessment of the risk of bias in each Cohort study using the Newcastle–Ottawa scale.
| Study | Selection(0-4) | Comparablility (0-2) | Outcome(0-3) | Total | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| REC | SNEC | AE | DO | SC | AF | AO | FU | AFU | ||
| Chen TF | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 7 |
| Hiltermann TJ | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 7 |
| Sher YP | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 7 |
| Hofman V | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
| Hou JM | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 6 |
| Igawa S | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 6 |
| Shi WJ | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 6 |
| Yamashita Y | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 6 |
| Yie SM | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
| Yoon SO | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
| Krebs MG | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 5 |
| Naito T | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Nieva J | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 5 |
| Juan O | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 5 |
| Bayarri-Lara C | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 5 |
| Chen X | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Hirose T | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 5 |
| Ji JL | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Peck K | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Sheu CC | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Wang B | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Wu C | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Feng YQ | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Lin XM | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Qian Z | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 5 |
| Lou JT | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 4 |
| Xu YH | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 4 |
| Huang TH | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 4 |
| Li J | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 4 |
| Zhao SW | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 4 |