Table 3.

Probability of Being on Frontier: Generalized Estimating Equation with Instrumental Variables

	DEA 1	DEA 2	DEA 3
Total grant revenue (%)	−0.941	−3.012	−1.987
Medicaid managed care revenue (%)	−0.030	−1.023	−0.301
Ratio NP+PA/physician	−0.551	0.007	−0.437
Ln staff hours	−0.459*	−0.615**	−0.550***
Actual versus expected utilization	0.376	0.390	0.498
Actual versus expected diabetes	−0.155	−0.102	−0.104
Actual versus expected hypertension	0.035	0.188	−0.052
Patients 1–5 years old (%)	2.637	−0.735	1.003
Patients 65 and older (%)	0.610	−1.469	−0.236
Black (%)	−0.375	−0.035	−0.116
Non-English (%)	0.234	0.137	0.229
Medicaid (%)	0.144	−0.059	0.010
Uninsured (%)	0.224	0.806	0.678
Urban	−0.059	−0.003	−0.032
Ln county household income	−0.553*	−0.101	−0.339
Constant	10.478**	8.332*	9.709***

^***p < .001,

^**p < .01,

^*p < .05.