TABLE 2.
Discrete-Time Proportional Hazard Models on Trauma Center Closures Between 1990 and 2005
| Hazard Ratio | (95% CI) | P | ||
|---|---|---|---|---|
| Financial pressure measures | ||||
| Profit margin | ||||
| Hospital with (−5, 5)% margin | 1.000 | — | — | — |
| Hospital with < −5% profit margin | 1.384‡ | 1.055 | 1.815 | 0.02 |
| Hospital with >5% profit margin | 1.010 | 0.753 | 1.355 | 0.95 |
| Medicare payment generosity | ||||
| Receive average reimbursement | 1.000 | — | — | — |
| Received less generous Medicare reimbursement than average | 1.024 | 0.751 | 1.397 | 0.88 |
| Received more generous Medicare reimbursement than average | 0.578* | 0.374 | 0.892 | 0.01 |
| Medicaid payment generosity | ||||
| Hospitals in states with average Medicaid physician payment | 1.000 | — | — | — |
| Hospitals in states with below average Medicaid physician payment | 1.237 | 0.867 | 1.766 | 0.24 |
| Hospitals in states with above average Medicaid physician payment | 0.939 | 0.697 | 1.264 | 0.68 |
| HMO penetration level | ||||
| Low HMO markets | 1.000 | — | — | — |
| Medium HMO markets | 1.628* | 1.167 | 2.270 | 0.00 |
| High HMO markets | 2.059* | 1.416 | 2.994 | 0.00 |
| County population characteristics | ||||
| Minority population | ||||
| Low share (lower 1/3) | 1.000 | — | — | — |
| Medium share | 1.213 | 0.873 | 1.685 | 0.25 |
| High share | 1.693* | 1.173 | 2.444 | 0.01 |
| Population under poverty line | ||||
| Low share (lower 1/3) | 1.000 | — | — | — |
| Medium share | 1.048 | 0.743 | 1.479 | 0.79 |
| High share | 1.352 | 0.869 | 2.104 | 0.18 |
| Elderly population | ||||
| Low share (lower 1/3) | 1.000 | — | — | — |
| Medium share | 1.122 | 0.825 | 1.525 | 0.46 |
| High share | 1.278 | 0.908 | 1.800 | 0.16 |
| Uninsured population in 2000 | ||||
| 15% or lower | 1.000 | — | — | — |
| Greater than 15% | 0.908 | 0.653 | 1.262 | 0.57 |
| Other population characteristics | ||||
| Population (log transformed) | 1.034 | 0.894 | 1.197 | 0.65 |
| Cost of living (log transformed) | 0.656 | 0.197 | 2.187 | 0.49 |
| Hospital characteristics | ||||
| For-profit hospital | 1.975* | 1.421 | 2.745 | 0.00 |
| Government hospital | 0.856 | 0.575 | 1.275 | 0.45 |
| Teaching hospital | 0.444* | 0.286 | 0.690 | 0.00 |
| Member of a system | 1.276† | 0.982 | 1.660 | 0.07 |
| Case-mix index (log transformed) | 0.108* | 0.042 | 0.277 | 0.00 |
| Total visits to ED (log transformed) | 0.848* | 0.778 | 0.924 | 0.00 |
| Hospital market characteristics | ||||
| Presence of another trauma center within 15-mile radius | 0.833 | 0.630 | 1.102 | 0.20 |
| Share of Medicaid discharges twice as much as the average competitor within 15-mile radius | 0.840 | 0.531 | 1.327 | 0.45 |
| Competitive hospital market (hospital Herfindahl index <0.25) | 0.703‡ | 0.500 | 0.990 | 0.04 |
| Percent for-profit hospitals within 15-mile radius | 1.092 | 0.488 | 2.443 | 0.83 |
| Percent government hospitals within 15-mile radius | 1.561 | 0.616 | 3.958 | 0.35 |
| Observations | 9555 | |||
Census region and year indicators are included.
*
Significant at 1%,
†
significant at 10%,
‡
significant at 5%.