Table 3.
Demographic characteristics of the 2 ARC groups before and after matching for corneal astigmatism.
| Variables | Before matching | P value | After matching | P value | ||
| ARC-w | ARC-s | ARC-w | ARC-s | |||
|
| ||||||
| Age (y) | ||||||
| Mean ± SD | 64.75 ± 9.71 | 70.56 ± 9.55 | <0.001 | 69.21 ± 9.03 | 69.21 ± 9.03 | >0.99 |
| Range | 40, 103 | 40, 95 | 40, 94 | 40, 94 | ||
| M/F (n) | 3337/3728 | 1090/1661 | <0.001 | 1022/1459 | 1022/1459 | >0.99 |
|
| ||||||
| CYL (D) | ||||||
| Mean ± SD | 1.28 ± 1.04 | 1.01 ± 0.68 | <0.001 | 1.30 ± 1.03 | 0.98 ± 0.67 | <0.001 |
| Range | 0, 6.94 | 0.05, 6.59 | 0, 6.92 | 0.05, 6.59 | ||
| K1 (D) | 43.19 ± 1.50 | 43.77 ± 1.53 | <0.001 | 42.92 ± 1.51 | 43.76 ± 1.52 | <0.001 |
| K2 (D) | 44.24 ± 1.62 | 44.76 ± 1.56 | <0.001 | 43.97 ± 1.64 | 44.74 ± 1.55 | <0.001 |
| AL (mm) | 23.14 ± 0.95 | 23.45 ± 0.90 | <0.001 | 23.88 ± 0.90 | 23.48 ± 0.90 | <0.001 |
|
| ||||||
| Type of astigmatism | ||||||
| WTR (%) | 41.80 | 25.08 | 40.99 | 26.46 | ||
| ATR (%) | 38.89 | 58.26 | <0.001 | 40.71 | 56.74 | <0.001 |
| Oblique (%) | 19.31 | 16.66 | 18.30 | 16.80 | ||
ARC-w: age-related cataract in the western area; ARC-s: age-related cataract in the southern area; M: male; F: female; CYL: corneal astigmatism; K1: flat keratometry; K2: steep keratometry; AL: axial length; WTR: with the rule; ATR: against the rule; D: diopter.