Table 3.
Risk of bias, organized according to study design.
| Case-Control | NOS Scale | |||
|---|---|---|---|---|
| Selection | Comparibilty | Exposure | ||
| Byrd et al. | ** | * | *** | |
| Zhao et al. | ** | ** | *** | |
| Shin et al. | * | ** | *** | |
| Zhu et al. | ** | ** | ** | |
| Santos-Marcos et al. | **** | ** | *** | |
| Menni et al. | *** | ** | *** | |
| Chavez et al. | ** | ** | *** | |
| Miranda et al. | *** | ** | ** | |
| Pekkala et al. | **** | ** | ** | |
| Haro et al. | *** | ** | *** | |
| Min et al. | *** | * | *** | |
| Cohort | NOS Scale | |||
| Selection | Comparability | Outcome | ||
| Ott et al. | ** | ** | *** | |
| Cross-Sectional | AXIS | |||
| Intro | Methods | Results | Discussion/Ethics | |
| Fuhrman et al. | 1/1 | 7/11 | 4/5 | 4/4 |
| Flores et al. | 1/1 | 6/11 | 4/5 | 4/4 |
| Animal | SYRCLE’s | Bias Tool | ||
| Selection/Performance | Detection | Attrition | Reporting | |
| Choi et al. | 2/5 | 0/2 | 1/1 | 1/1 |
| Zhang et al. | 0/5 | 0/2 | 1/1 | 1/1 |
Risk of Bias table, graded according to NOS scale for assessing the quality of non-randomized studies for cohort studies and case-control studies in systematic reviews and meta-analyses. Further graded according to AXIS for cross-sectional studies and graded using the SYRCLE’s bias tool for animal studies.