Table 1.
Characteristics of patients who received radiation therapy according to ownership of the hospital where breast-conserving surgery was performed.
| Non-profit | For-profit | ||||
|---|---|---|---|---|---|
| N | % | N | % | p-value* | |
| Total | 22,496 | 2816 | |||
| Patient Characteristics | |||||
| Age at breast-conserving surgery | 0.53 | ||||
| 66–69 | 5964 | 26.5 | 765 | 27.2 | |
| 70–74 | 6673 | 29.7 | 834 | 29.6 | |
| 75–79 | 5209 | 23.2 | 619 | 22.0 | |
| 80–84 | 3412 | 15.2 | 428 | 15.2 | |
| 85–94 | 1238 | 5.5 | 170 | 6.0 | |
| Race | <.001 | ||||
| White | 20542 | 91.3 | 2517 | 89.4 | |
| Black | 1375 | 6.1 | 183 | 6.5 | |
| Other | 579 | 2.6 | 116 | 4.1 | |
| Year of surgery | 0.83 | ||||
| 2008 | 14610 | 64.9 | 1823 | 64.7 | |
| 2009 | 7886 | 35.1 | 993 | 35.3 | |
| Residence in metro county | 0.001 | ||||
| Yes | 18038 | 80.2 | 2330 | 82.7 | |
| No | 4458 | 19.8 | 486 | 17.3 | |
| Income quintile | <.001 | ||||
| Q1 (≤$33,208) | 4265 | 19.0 | 635 | 22.6 | |
| Q2 ($33,209–$39,659) | 4297 | 19.1 | 548 | 19.5 | |
| Q3 ($39,661–$47,295) | 4360 | 19.4 | 555 | 19.7 | |
| Q4 ($47,300–$60,118) | 4401 | 19.6 | 508 | 18.0 | |
| Q5 (≥$60,124) | 4422 | 19.7 | 467 | 16.6 | |
| Unknown | 751 | 3.3 | 103 | 3.7 | |
| Clinical characteristics | |||||
| Comorbidity | 0.72 | ||||
| 0 conditions | 12761 | 56.7 | 1584 | 56.3 | |
| 1–2 conditions | 7995 | 35.5 | 1021 | 36.3 | |
| ≥3 conditions | 1740 | 7.7 | 211 | 7.5 | |
| Tumor laterality | 0.41 | ||||
| Right-sided | 9715 | 43.2 | 1227 | 43.6 | |
| Left-sided | 10056 | 44.7 | 1228 | 43.6 | |
| Unknown | 2725 | 12.1 | 361 | 12.8 | |
| Axillary node dissection | 0.06 | ||||
| No | 6285 | 27.9 | 740 | 26.3 | |
| Yes | 16211 | 72.1 | 2076 | 73.7 | |
| Chemotherapy | 0.04 | ||||
| No chemotherapy | 19721 | 87.7 | 2429 | 86.3 | |
| Chemotherapy started in month prior through month after surgery | 920 | 4.1 | 115 | 4.1 | |
| Chemotherapy started in 31–365 days after surgery | 1855 | 8.3 | 272 | 9.7 | |
| Hospital admission** | 0.96 | ||||
| No | 19460 | 86.5 | 2435 | 86.5 | |
| Yes | 3036 | 13.5 | 381 | 13.5 | |
| Screening mammogram** | 0.06 | ||||
| No | 5102 | 22.7 | 683 | 24.3 | |
| Yes | 17394 | 77.3 | 2133 | 75.8 | |
| Flu shot** | 0.02 | ||||
| No | 9390 | 41.7 | 1242 | 44.1 | |
| Yes | 13106 | 58.3 | 1574 | 55.9 | |
| Visit to primary care physician** | 0.12 | ||||
| No | 686 | 3.1 | 71 | 2.5 | |
| Yes | 21810 | 97.0 | 2745 | 97.5 | |
| Hospital characteristics | |||||
| Hospital volume*** | <0.001 | ||||
| Q1 (1–7) | 4170 | 18.5 | 855 | 30.4 | |
| Q2 (8–14) | 4284 | 19.0 | 862 | 30.6 | |
| Q3 (15–22) | 4347 | 19.3 | 445 | 15.8 | |
| Q4 (23–38) | 5013 | 22.3 | 338 | 12.0 | |
| Q5 (39–142) | 4682 | 20.8 | 316 | 11.2 | |
| Health system characteristics | |||||
| State certificate of need for radiation facility | <0.001 | ||||
| No | 11820 | 52.5 | 1773 | 63.0 | |
| Yes | 10676 | 47.5 | 1043 | 37.0 | |
| HRR-level two-year mammography rate among female Medicare enrollees 67–69, in quintiles | <0.001 | ||||
| Q1 (50.1–59.7) | 3941 | 17.5 | 793 | 28.2 | |
| Q2 (59.8–62.4) | 4400 | 19.6 | 706 | 25.1 | |
| Q3 (62.4–64.9) | 4652 | 20.7 | 468 | 16.6 | |
| Q4 (65.0–68.4) | 4762 | 21.2 | 441 | 15.7 | |
| Q5 (68.4–76.1) | 4741 | 21.1 | 408 | 14.5 | |
| Radiation oncologist density per 100,000 residents, in quintiles | <0.001 | ||||
| Q1 (0.2–1.0) | 4397 | 19.6 | 688 | 24.4 | |
| Q2 (1.0–1.1) | 4078 | 18.1 | 660 | 23.4 | |
| Q3 (1.1–1.2) | 4531 | 20.1 | 624 | 22.2 | |
| Q4 (1.2–1.4) | 4818 | 21.4 | 293 | 10.4 | |
| Q5 (1.4–2.5) | 4672 | 20.8 | 551 | 19.6 | |
*
P-value is for chi-square test of the association between each covariate and profit status
**
In year prior to breast-conserving surgery
***
Hospital volume is defined as the number of patients in our sample who received breast-conserving surgery at each hospital during the study period