Table 3.
Regression results: CCOP, network, and environmental factors associated with CCOP trial accrual.
| Variable | Total accrual
|
Treatment accrual
|
CP/C accrual
|
|||
|---|---|---|---|---|---|---|
| β | (S.E.) | β | (S.E.) | β | (S.E.) | |
| CCOP characteristics | ||||||
| Num. of active CCOP MDs | 2.575*** | (0.984) | 1.322*** | (0.344) | 0.862 | (0.514) |
| Num. of CCOP components | −3.063 | (3.468) | −1.151 | (1.231) | 0.369 | (1.392) |
| Num. of active IRBs | −6.388 | (6.708) | 0.639 | (2.393) | −6.292 | (4.038) |
| Num. of CCOP components num. of active IRBs | 0.951 | (0.697) | 0.096 | (0.249) | 0.695* | (0.305) |
| Num. of CCOP or RB meetings attended | 0.356 | (0.373) | 0.121 | (0.132) | 0.216 | (0.168) |
| Low physician accrual equity | – | – | – | – | – | – |
| Medium physician accrual equity | 0.749 | (10.505) | −6.962* | (3.746) | −3.664 | (9.098) |
| High physician accrual equity | 14.563 | (12.456) | −10.796 | (4.445) | 10.074 | (10.557) |
| CCOP-RB network characteristics | ||||||
| Num. of affiliated RBs | 2.838 | (1.843) | −0.250 | (0.658) | 3.546* | (1.612) |
| Num. of total trials | 2.291*** | (0.480) | – | – | – | – |
| Num. of treatment trials | – | – | 1.388*** | (0.209) | – | – |
| Num. of CP/C trials | – | – | – | – | 5.607*** | (0.893 |
| Environmental characteristics | ||||||
| Hospital competition (1-HHI) | 252.382 | (215.919) | 135.828 | (76.580) | −92.949* | (45.067) |
| HMO penetration | −60.606 | (76.947) | −27.235 | (27.420) | −20.235 | (48.148) |
| Proportion of MSA uninsured | −71.556 | (260.821) | 129.267 | (93.093) | −193.766 | (152.635) |
| Low proportion of hospitals with in MSA medical school affiliation | – | – | – | – | – | – |
| Medium proportion of hospitals in MSA with medical school affiliation | −19.450 | (1.210) | 7.930 | (1.380) | −12.250 | (1.060) |
| High proportion of hospitals in MSA with medical school affiliation | −57.115* | (2.490) | −5.087 | (0.062) | −30.993* | (2.310) |
| State insurance mandate | 1.067 | (17.372) | 3.862 | (6.201) | −15.420 | (11.909) |
| Time variables | ||||||
| 2000–2001 | – | – | – | – | – | – |
| 2002–2003 | −27.571* | (11.459) | −19.986*** | (4.109) | −8.435 | (10.202) |
| 2004–2005 | −44.152*** | (12.110) | 9.280*** | (4.291) | −58.754*** | (10.871) |
| 2006–2007 | −57.296*** | (13.166) | −13.058** | (4.694) | −49.680*** | (11.373) |
| Intercept | −46.030 | (0.260) | −56.170 | (0.890) | 152.000*** | (3.370) |
N=335, G=45.
F test for joint significance of equality F(2, 292)=1.00 F(2, 292)=3.07 chi2(2)=2.14.
*
p<0.05.
**
p<0.01.
***
p<0.001.