Table 3. Three-years cumulative risk of severe vascular events among the patients by treatment modality.(n = 22931).

Stratum	No.		%of Stratum		Risk(%)
	Without surgery	TKA +	Without surgery	TKA	Without surgery	TKA	p value
1	2207	2380	0.48	0.52	23.9	16.1	<0.001
2	1706	2880	0.37	0.63	18.0	10.3	<0.001
3	1500	3085	0.33	0.67	18.7	10.6	<0.001
4	1317	3270	0.29	0.71	3.6	2.3	0.013
5	838	3748	0.18	0.82	0.2	0.2	0.994
Total	7568	15363			15.4	7.1	<0.001

+TKA, total knee arthroplasty.

Stratum 1 had the strongest propensity for not receiving TKA; stratum 5, for receiving TKA. Conchran-Mantel-Haenszel statistics; adjusted odds ratio = 0.56, 95% confidence interval = 0.51–0.61.