Summary of Downs Black Scale for cohort studies
| Risk of bias | Reference 4 | Reference 22 | Reference 23 | Reference 24 (inter) | Reference 24 (intra) |
|---|---|---|---|---|---|
| Reporting (accuracy and detail) | 9/11 | 8/11 | 8/11 | 9/11 | 9/11 |
| External validity (representativeness) | 3/3 | 1/3 | 1/3 | 2/3 | 1/3 |
| Internal validity (bias) | 3/7 | 3/7 | 3/7 | 3/7 | 3/7 |
| Internal validity (selection bias) | 2/6 | 1/6 | 3/6 | 2/6 | 2/6 |
| Power | 2/5 | 0/5 | 0/5 | 2/5 | 0/5 |
| Total | 19/32 | 13/32 | 15/32 | 18/32 | 15/32 |