Table 6.
Instrumental variable estimates of Cox proportional hazard survival models*
| Variable label | Prostate-specific survival |
All-cause survival |
||
| HR (95% CI) | P† | HR (95% CI) | P† | |
| Watchful waiting | 0.725 (0.078 to 6.729) | .777 | 1.094 (0.462 to 2.593) | .838 |
| Residual (waiting)—from Supplementary Table 2, available online | 2.442 (0.215 to 27.71) | .471 | 1.491 (0.64 to 3.475) | .354 |
| Age at diagnosis 70–74 vs 66–69 y | 1.536 (1.144 to 2.061) | .004 | 1.678 (1.509 to 1.865) | <.001 |
| Black non-Hispanic vs white non-Hispanic | 1.125 (0.725 to 1.745) | .599 | 1.367 (1.181 to 1.583) | <.001 |
| Hispanic vs white non-Hispanic | 0.868 (0.542 to 1.389) | .554 | 0.933 (0.799 to 1.09) | .381 |
| Other race vs white non-Hispanic | 0.504 (0.259 to 0.982) | .044 | 0.7 (0.573 to 0.855) | .001 |
| Married vs single | 0.743 (0.496 to 1.112) | .149 | 0.662 (0.573 to 0.765) | <.001 |
| Stage T2 vs T1 | 1.197 (0.946 to 1.515) | .135 | 0.976 (0.898 to 1.061) | .568 |
| Grade moderately differentiated vs well differentiated | 1.969 (1.008 to 3.843) | .047 | 0.848 (0.728 to 0.988) | .035 |
| Grade poorly differentiated vs well differentiated | 8.079 (3.612 to 18.071) | <.001 | 1.227 (0.975 to 1.546) | .082 |
| Grade unknown vs well differentiated | 6.491 (2.312 to 18.224) | <.001 | 1.067 (0.763 to 1.493) | .705 |
| NCI comorbidity index of 0 vs unknown | 0.322 (0.148 to 0.703) | .004 | 0.668 (0.462 to 0.965) | .031 |
| NCI comorbidity index of 1 vs unknown | 0.354 (0.152 to 0.825) | .016 | 1.095 (0.752 to 1.594) | .637 |
| NCI comorbidity index of ≥2 vs unknown | 0.488 (0.213 to 1.117) | .090 | 1.845 (1.277 to 2.667) | .001 |
| Inflation-adjusted reimbursement in the year before diagnosis (2003 prices) | 1 (1 to 1) | .704 | 1 (1 to 1) | <.001 |
| Any inpatient, outpatient, or carrier claims in year before diagnosis vs no claims | 1.349 (0.583 to 3.119) | .484 | 0.989 (0.677 to 1.444) | .953 |
| Diagnosed in 1997 vs 1996 | 1.185 (0.857 to 1.637) | .304 | 1.104 (0.979 to 1.244) | .106 |
| Diagnosed in 1998 vs 1996 | 0.772 (0.522 to 1.142) | .195 | 0.929 (0.814 to 1.061) | .279 |
| Diagnosed in 1999 vs 1996 | 0.987 (0.653 to 1.492) | .952 | 0.928 (0.803 to 1.073) | .313 |
| Diagnosed in 2000 vs 1996 | 1.176 (0.741 to 1.866) | .492 | 0.998 (0.848 to 1.175) | .983 |
| Diagnosed in 2001 vs 1996 | 0.733 (0.453 to 1.187) | .207 | 0.851 (0.733 to 0.988) | .034 |
| Diagnosed in 2002 vs 1996 | 1.061 (0.632 to 1.783) | .822 | 0.844 (0.711 to 1.002) | .052 |
| Diagnosed in 2003 vs 1996 | 0.871 (0.441 to 1.72) | .690 | 0.723 (0.592 to 0.884) | .002 |
*
CI = confidence interval; HR = hazard ratio; NCI = National Cancer Institute.
†
A two-sided Wald χ2 test was used.