Internal consistency (Cronbach α) and test–retest reliability of CHI-VFQ-25 subscales
| Subscale | Cronbach α | Test–retest reliability |
| General Health | 0.50 | 0.97 |
| General Vision | 0.73 | 0.96 |
| Ocular Pain | 0.74 | 0.95 |
| Near Activities | 0.84 | 0.96 |
| Distance Activities | 0.90 | 0.95 |
| Social Functioning | 0.72 | 0.96 |
| Mental Health | 0.81 | 0.98 |
| Role Difficulties | 0.81 | 0.98 |
| Dependency | 0.81 | 0.97 |
| Driving | 0.68 | NA† |
| Colour Vision | NA* | 0.92 |
| Peripheral Vision | NA* | 0.92 |
*Cronbach α cannot be calculated in subscales with only one item.
†Too few cases (N = 1) for the analysis.
NA, not applicable.