Table 3.

Parameter Estimates from Sensitivity Analysis 2, Interrupted Time Series ARIMA Models with Demographic Covariates

	40–49 year-old ARIMA model				50–64 year-old ARIMA model
Parameter	Estimate	Standard error	T-value	p-value	Estimate	Standard error	T-value	p-value
B0, intercept	−438.50425	79.0346	−5.55	<0.0001	−809.21	159.9385	−5.06	<0.0001
AR(2)	0.28674	0.1113	2.58	0.0117	0.23472	0.1114	2.11	0.038
AR(3)	0.43900	0.1064	4.13	<0.0001	0.3499	0.1092	3.21	0.0019
AR(10)	−0.38645	0.1068	−3.62	0.0005	−0.36615	0.1091	−3.36	0.0012
AR(12)	0.74187	0.0901	8.24	<0.0001	0.75365	0.0879	8.57	<0.0001
B1, time	−0.24930	0.10791	−2.31	0.0233	−0.31751	0.1175	−2.7	0.0083
B2, intervention	−3.18311	1.6268	−1.96	0.0537	−2.63915	2.1778	−1.21	0.2289
B3, timeafterintervention	0.27036	0.1063	2.54	0.0128	0.27778	0.1153	2.41	0.0181
B4, pulseshift	−3.10182	1.2241	−2.53	0.0131	−4.96309	1.6826	−2.95	0.0041
Mean Age	9.80870	1.7398	5.64	<0.0001	14.60742	2.8411	5.14	<0.0001
Percent PPO	71.94610	26.7536	2.69	0.0086	70.13133	31.6626	2.21	0.0294

Time, change in trend across time; Intervention, after guideline change in level; Timeafterintervention, after guideline change in linear trend; Pulseshift, change in level of screening rates in the 2 months after guideline; PPO, preferred provider organization.