Table II.

Age distribution of KOA.

Parameter		Total n (%)	KOA cases n (%)	KOA-free cases n (%)	P-value
Age groups	< 40 years	273 (100%)	70 (25.6%)	203 (74.4%)	<0.0001**** df = 72.53, 3
	40 – 50 years	75 (100%)	45 (60%)	30 (40%)
	51 – 60 years	48 (100%)	38 (79.2%)	10 (20.8%)
	61 – 90 years	14 (100%)	10 (71.4%)	4 (29.6%)
	Total	410 (100%)	163 (39.7%)	247 (60.3%)
Gender	Male	328 (100%)	102 (31%)	226 (69%)	<0.0001**** df=51.34, 1
	Female	82 (100%)	61 (74.4%)	21 (25.6%)
	Total	410 (100%)	163 (39.7%)	247 (60.3%)