Table 2.

%Bias, coverage and relative efficiency for estimated treatment effect on cost under different PS estimation methods

	Correct PS			Misspecified PS			SL PS
gamma model	%bias	Coverage	MSER	%bias	Coverage	MSER	%bias	Coverage	MSER
naive regression	−9.52	0.67	5.81
covariates adjustmt: normal	6.66	0.92	5.18	7.50	0.88	7.80	5.01	0.92	3.85
covariates adjustmt: lognormal	−21.98	0.22	1.35	−22.67	0.12	2.04	−22.19	0.72	1.26
covariates adjustmt: gamma	0.30	0.94	2.07	4.13	0.94	3.12	0.30	0.96	1.53
stratification	2.85	0.91	10.54	32.58	0.77	20.65	1.77	0.94	5.94
IPTW	0.76	0.96	14.25	46.71	0.28	21.48	0.62	0.93	8.95
IPTW: normalized	−0.36	0.94	1.83	8.88	0.90	2.76	0.21	0.92	1.58
DR: normal	0.61	0.94	1.46	0.75	0.93	1.31	0.30	0.94	1.07
DR: lognormal	−0.71	0.94	1.45	8.91	0.89	1.05	0.38	0.96	0.93
DR: gamma	0.29	0.93	1.53	0.19	0.93	0.94	0.09	0.95	0.90
DR: SL in regression model	0.48	0.92	1 (ref)	3.10	0.94	1 (ref)	0.02	0.90	1 (ref)
mixed
naive regression	−48.82	0.29	6.70
covariates adjustmt: normal	44.45	0.54	1.74	45.15	0.54	2.27	42.34	0.60	2.21
covariates adjustmt: lognormal	−16.81	0.85	2.54	−26.51	0.85	5.09	−19.18	0.83	4.21
covariates adjustmt: gamma	23.84	0.79	1.46	15.84	0.79	1.84	21.56	0.84	1.71
stratification	12.64	0.91	5.49	15.47	0.77	16.84	9.25	0.95	3.57
IPTW	8.57	0.97	9.47	10.57	0.97	23.13	4.23	0.92	6.00
IPTW: normalized	−1.00	0.94	1.10	−2.00	0.94	1.88	−0.80	0.92	1.05
DR: normal	−1.81	0.96	1.74	−8.07	0.96	1.03	−1.21	0.95	1.06
DR: lognormal	−2.00	0.97	3.85	−6.77	0.98	1.86	−1.24	0.96	1.07
DR: gamma	−2.07	0.97	1.82	−1.93	0.95	0.97	−0.34	0.95	1.05
DR: SL in regression model	−0.18	0.98	1 (ref)	−5.72	0.97	1 (ref)	−0.02	0.97	1 (ref)