Prevalence of refractive error, astigmatic axis, and presenting visual impairment in participants aged 6–7 years and 12–13 years in the Ireland Eye Study
| Prevalence, right eye | n | 6–7 years, % (CI) | n | 12–13 years, % (CI) |
| Myopia | 24 | 3.3 (2.2 to 4.9) | 179 | 19.9 (17.4 to 22.7) |
| Hyperopia | 182 | 25.0 (21.9 to 28.3) | 80 | 8.9 (7.2 to 11.0) |
| Astigmatism | 140 | 19.2 (16.5 to 22.3) | 143 | 15.9 (13.5 to 18.4) |
| Astigmatic axis | ||||
| WTR | 112 | 80.0 (72.2 to 86.1) | 109 | 77.3 (69.3 to 83.7) |
| ATR | 8 | 5.7 (2.7 to 11.3) | 13 | 9.2 (5.2 to 15.6) |
| OBL | 20 | 14.3 (9.2 to 21.4) | 19 | 13.5 (8.5 to 20.5) |
| PVI (better eye) | 27 | 3.7 (2.5 to 5.4) | 30 | 3.4 (2.3 to 4.8) |
| PVI (either eye) | 65 | 8.9 (7.0 to 11.3) | 75 | 8.4 (6.7 to 10.4) |
ATR, against-the-rule; OBL, oblique; PVI, presenting visual impairment; WTR, with-the-rule.