Table 2.

Association of warfarin use with all-cause mortality

	Events (%)		Absolute risk difference*	Hazard ratio (95% confidence interval)	P value
	No warfarin	Warfarin
All-cause mortality
Before matching (N=2248)	n=347	n=1901
Unadjusted	97 (28%)	365 (19%)	− 9%	0.71 (0.57–0.89)	0.003
Multivariable-adjusteda	---	---		0.70 (0.54–0.91)	0.007
Propensity-adjustedb	---	---		0.67 (0.52–0.87)	0.003
After matching (N=843)	n=227	n=616
Propensity-matched	74 (33%)	112 (18%)	− 14%	0.58 (0.43–0.77)	<0.001

^*Absolute risk difference was calculated by subtracting the percentage of events in the warfarin group from that of the no-warfarin group (before values were rounded)

^aAdjusted for all 45 baseline characteristics

^bAdjusted for propensity score.