Table 4.

Subgroup analysis stratified by age

Event	aHR (95% CI)	P for interaction
Superficial keratopathy		0.002*
age<60	0.976(0.939-1.014)
age 60-69	1.015(0.979-1.052)
age ≥70	1.067(1.033-1.102)*
Infectious keratitis		0.752
age<60	1.040(0.960-1.126)
age 60-69	1.007(0.924-1.099)
age ≥70	1.019(0.942-1.103)

aHR: adjusted hazard ratio, CI: confidence interval

* denotes a significant difference