Table 3.
Results of quality assessment by NOS for case-control studies
| Study | Selection | Comparability | Exposure | Scores | |||||
|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | ||
| Chan et al. | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 8 |
| Jarmalaite et al. | ★ | ★ | - | ★ | ★ | ★ | ★ | ★ | 6 |
| Tada et al. | ★ | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |
| Nakagawa et al. | ★ | ★ | ★ | ★ | - | ★ | ★ | ★ | 6 |
| Lin et al. | ★ | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |
| Jablonowski et al. | ★ | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |
| Valenzuela et al. | ★ | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |
| Ali et al. | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 8 |
| Hauser et al. | ★ | ★ | ★ | ★ | ★ | ★ | ★ | ★ | 7 |
| Scher et al. | ★ | ★ | - | ★ | - | ★ | ★ | ★ | 5 |
1. Adequate definition of cases; 2. Representativeness of cases; 3. Selection of controls; 4. Definition of controls; 5. Control for important factor; 6. Ascertainment of Exposure; 7. Same method to ascertain for cases and controls; 8. Non-response rate.