Table III.

Logistic regression model comparing method of venous thromboembolism prophylaxis in bilateral total knee arthroplasty

Variable	PE model		p-value*	Combined VTE model		p-value*
	Exp RR	95% CI		Exp RR	95% CI
Aspirin	0.44	0.25 to 0.78	0.005	0.62	0.38 to 1.01	0.052
NIS VTE score (per 10 points)†	1.26	1.14 to 1.38	< 0.0001	1.23	1.13 to 1.34	< 0.0001

*p-values calculated using logistic regression †NIS VTE score excluding bilateral joint as a risk factor PE, pulmonary embolism; VTE, venous thromboembolism; Exp RR, exponential relative risk; CI, confidence interval; NIS, National Inpatient Sample