Table 3. Estimation Results of the Two-Part Model of the Frequency of Nonemergent Emergency Department (ED) Visits

	Binary Hurdle Model (Logit)		Zero-Truncated Negative Binomial Model
	Coefficient	t Value	Coefficient	t Value
Constant	−2.382^*	−2.81	−17.329^*	−5.52
Predisposing characteristics
Age, years
45–64	−0.651^*	−7.76	−0.490^*	−2.15
≥65	−0.738^*	−5.39	−0.717	−1.93
Female sex	0.339^*	4.51	0.244	1.23
Race
Black	0.386^*	4.06	−0.701^*	−3.33
Other	−0.123	−0.79	−0.853^*	−2.51
Hispanic ethnicity	−0.010	−0.10	0.532^*	2.00
Education
GED/high school	0.155	1.47	0.490^*	2.08
Bachelor's degree or more	−0.078	−0.57	0.825^*	2.70
Employed	−0.043	−0.44	0.187	0.93
Marital status
Widowed	0.035	0.20	0.479	1.37
Divorced	0.059	0.51	−0.215	−0.73
Separated	0.313^*	1.98	0.248	0.56
Never married	0.126	1.29	0.173	0.79
Able to speak English	0.416^*	2.54	0.926	1.67
More likely to take risks	0.061	0.61	0.206	0.94
Can overcome illness without medical help	−0.167	−1.71	−0.264	−1.15
Enabling resources
Income (% of poverty level)
<100 (poor)	0.716^*	5.15	0.177	0.59
100–199 (low income)	0.495^*	3.98	0.098	0.41
200–399 (middle income)	0.279^*	2.30	0.321	1.23
Health insurance
Public	0.177	1.60	0.294	1.36
Uninsured	0.064	0.54	0.503	1.92
Region
Midwest	0.285^*	2.23	0.028	0.10
South	0.088	0.67	−0.188	−0.71
West	0.148	1.11	−0.033	−0.11
Urban MSA	−0.090	−0.86	0.295	1.34
Need factors
Health status
Very good	0.280^*	2.07	−0.350	−0.95
Good	0.777^*	5.57	0.120	0.37
Fair	1.047^*	6.31	0.713	1.87
Poor	1.689^*	8.26	0.857^*	1.96
Mental health
Very good	−0.216^*	−2.09	0.234	0.88
Good	−0.086	−0.74	0.220	1.00
Fair	0.045	0.32	−0.185	−0.63
Poor	0.045	0.22	0.412	0.97
Hypertension	−0.105	−1.10	−0.233	−0.91
Coronary heart disease	−0.103	−0.70	−0.104	−0.25
Angina	0.119	0.52	1.044^*	2.02
Myocardial infarction	−0.132	−0.73	0.224	0.49
Other heart disease	−0.011	−0.09	−0.647	−1.94
Stroke	−0.468^*	−2.85	−0.539	−1.46
Emphysema	−0.041	−0.22	−0.211	−0.66
High cholesterol	0.054	0.55	0.724^*	3.36
Diabetes	−0.025	−0.21	0.356	1.39
Arthritis	−0.066	−0.73	0.126	0.67
Asthma	−0.335^*	−3.42	−0.310	−1.52
Patient-provider communication
USC asks about other treatments	0.164	1.79	−0.152	−0.76
USC shows respect for treatments	0.062	0.69	0.161	0.78
USC asks person to help decide	−0.075	−0.83	0.179	0.90
USC explains options to person	−0.154	−1.09	−0.316	−0.90
USC speaks language or provides interpreter services	−0.344	−0.83	−2.063^*	−2.28
Access
Transportation to USC
Is driven	0.047	0.39	0.209	0.87
Public transportation	0.155	0.90	0.065	0.20
Walks or other	−0.161	-0.66	0.715	1.47
Time to USC, minutes
15–30	−.077	−0.99	−0.211	−1.13
31–60	−0.044	−0.33	0.418	1.20
>60	0.262	1.13	0.974^*	2.43
USC has office hours on nights and weekends	0.051	0.62	0.324^*	2.02
Difficulty getting to USC	0.323^*	2.45	−0.144	−0.53
Difficulty in contacting USC by phone	0.144	1.50	−0.297	−1.18
Difficulty in contacting USC after hours	0.180^*	2.29	0.387^*	1.96

↵* P < .05.
MSA, metropolitan statistical area; USC, usual source of care.