Table 2.

Simulation statistics for the natural indirect effect decomposition with mediation formula approach for continuous mediator on data generated from ZINB/logit-log model, standard deviation of mediator and dispersion parameters are all 0.5, n = 100 per group.

True τ (M(1), M(0))	True DE	True IE	True IEB	Est IE	Est IEB τ (M(1), M(0)) = 0.0		Est IEB τ (M(1), M(0)) = 0.4		Est IEB τ (M(1), M(0)) = 0.9
					Bias	CP (%)	Bias	CP (%)	Bias	CP (%)
0.0	−0.113	−0.780	−0.057	−0.843	−0.010	94.6	−0.007	94.6	−0.004	94.8
	−0.092	−0.828	−0.533	−0.826	0.009	94.3	0.040	93.5	0.079	91.8
	−0.117	−0.775	−0.742	−0.768	0.007	94.6	0.010	95.1	0.014	95.3
	−1.371	−0.741	−0.053	−0.784	−0.007	94.0	−0.005	93.9	−0.002	93.9
	−1.171	−0.817	−0.530	−0.839	−0.006	94.0	0.028	93.6	0.072	91.8
	−0.857	−0.761	−0.735	−0.766	0.010	94.7	0.016	94.6	0.022	94.2
0.4	−0.113	−0.780	−0.052	−0.830	−0.022	93.7	−0.019	93.9	−0.016	93.9
	−0.092	−0.828	−0.501	−0.842	−0.034	95.2	−0.003	95.3	0.038	94.6
	−0.117	−0.775	−0.738	−0.789	0.003	95.3	0.008	95.3	0.014	95.3
	−1.371	−0.741	−0.047	−0.777	0.005	94.2	0.005	94.4	0.005	94.2
	−1.171	−0.817	−0.495	−0.836	−0.041	95.1	−0.007	94.7	0.037	94.1
	−0.857	−0.761	−0.731	−0.752	0.006	93.9	0.009	94.1	0.012	93.5
0.9	−0.113	−0.780	−0.046	−0.825	0.005	95.7	0.005	95.7	0.006	95.6
	−0.092	−0.828	−0.460	−0.822	−0.057	95.3	−0.027	95.4	0.012	95.0
	−0.117	−0.775	−0.733	−0.789	−0.011	95.7	−0.006	95.6	−0.001	95.2
	−1.371	−0.741	−0.040	−0.800	−0.035	94.7	−0.031	94.6	−0.025	94.6
	−1.171	−0.817	−0.452	−0.837	−0.089	95.0	−0.054	95.6	−0.010	95.4
	−0.857	−0.761	−0.726	−0.760	−0.003	94.9	0.001	95.0	0.006	94.9