Quality of cohort studies assessed based on modified Newcastle-Ottawa scaling.
| A. Selection | B. Comparability of Cohorts | C. Outcome | ||||||
| Study | Representiveness/Effectiveness of Exposed Cohort | Selection of Nonexposed | Ascertainment of Exposure | Outcome Not Present at Start | Adjustment for Confounding/Bias?Adjustment ≥3 = YesAdjustment ≤3 = No | Assessment of Outcome | Length of Follow-Up Appropriate? | Adequate of Follow-Up of Cohort? |
| Kim et al, 201210 | YES | YES | YES | YES | YES | YES | YES | YES |
| Stoker et al, 20135 | YES | YES | YES | YES | YES | YES | YES | YES |
| Ravindra et al, 20152 | YES | YES | YES | YES | YES | YES | YES | YES |
| Martins et al, 201711 | YES | YES | YES | YES | NO | YES | YES | YES |
| Ravindra et al, 201912 | YES | YES | YES | YES | YES | YES | YES | YES |
| Donnally et al, 201913 | YES | YES | YES | YES | YES | YES | YES | YES |
| Xu et al, 202014 | YES | YES | YES | YES | NO | YES | YES | YES |