Table 2.

Simulated Data and Calculated Values for DR₁, DR₀^a

	Covariate Strata
	Z1 = 0				Z1 = 1
	Z2 = 0		Z2 = 1		Z2 = 0		Z2 = 1
	Z3 = 0	Z3 = 1	Z3 = 0	Z3 = 1	Z3 = 0	Z3 = 1	Z3 = 0	Z3 = 1
Total no.	3,960	2,040	1,890	610	740	260	410	90
p(X = 1|Z)	0.545	0.118	0.762	0.262	0.730	0.231	0.878	0.444
p(Y = 1|Z)	0.2	0.1	0.3	0.2	0.3	0.2	0.5	0.4
Unexposed (X = 0)
No.	1,800	1,800	450	450	200	200	50	50
Y = 1	360	180	135	90	60	40	25	20
Y = 0	1,440	1,620	315	360	140	160	25	30
DR0|Y = 1	1.96	1.12	3.24	1.28	2.89	1.24	4.60	1.48
DR0|Y = 0	−0.24	−0.01	−0.96	−0.07	−0.81	−0.06	−3.60	−0.32
DR1	0.2	0.1	0.3	0.2	0.3	0.2	0.5	0.4
Exposed (X = 1)
No.	2,160	240	1,440	160	540	60	360	40
Y = 1	432	24	432	32	162	12	180	16
Y = 0	1,728	216	1,008	128	378	48	180	24
DR1|Y = 1	1.67	7.75	1.22	3.25	1.26	3.67	1.07	1.75
DR1|Y = 0	−0.17	−0.75	−0.09	−0.56	−0.11	−0.67	−0.07	−0.50
DR0	0.2	0.1	0.3	0.2	0.3	0.2	0.5	0.4

Abbreviation: DR, doubly robust.

^aDR₀ = estimated value for Y under X = 0 for individual i; DR₁ = estimated value for Y under X = 1 for individual i; X = exposure, Y = outcome, Z₁−Z₃ = covariates.