TABLE 1.
Baseline characteristics for patients ≥40 years, stratified by center volume and facility type.
| Center volume (%) | Facility type (%) | |||||||
|---|---|---|---|---|---|---|---|---|
| Overall | Low ≤91% | High >91% | p | Community | Academic | p | ||
| n | 14 593 | 7004 | 7589 | 4885 | 9708 | |||
| Facility type (%) | Community program | 4885 (33.5) | 4227 (60.4) | 658 (8.7) | <0.001 | |||
| Academic program | 9708 (66.5) | 2777 (39.6) | 6931 (91.3) | |||||
| Center volume (%) | Low volume ≤91% | 7004 (48.0) | 4227 (86.5) | 2777 (28.6) | <0.001 | |||
| High volume >91% | 7589 (52.0) | 658 (13.5) | 6931 (71.4) | |||||
| Age at diagnosis (median [IQR]) | 60.0 [50.0, 70.0] | 62.0 [52.0, 73.0] | 58.0 [49.0, 67.0] | <0.001* | 62.0 [52.0, 73.0] | 59.0 [50.0, 68.0] | <0.001* | |
| Sex (%) | Male | 7646 (52.4) | 3664 (52.3) | 3982 (52.5) | 0.862 | 2557 (52.3) | 5089 (52.4) | 0.944 |
| Female | 6947 (47.6) | 3340 (47.7) | 3607 (47.5) | 2328 (47.7) | 4619 (47.6) | |||
| Race (%) | White | 12 526 (86.8) | 6030 (87.0) | 6496 (86.6) | 0.887 | 4336 (89.5) | 8190 (85.4) | <0.001 |
| Black | 1171 (8.1) | 553 (8.0) | 618 (8.2) | 279 (5.8) | 892 (9.3) | |||
| Asian | 457 (3.2) | 220 (3.2) | 237 (3.2) | 147 (3.0) | 310 (3.2) | |||
| Other | 284 (2.0) | 132 (1.9) | 152 (2.0) | 83 (1.7) | 201 (2.1) | |||
| Ethnicity (%) | NonSpanish/NonHispanic | 11 954 (85.8) | 5815 (88.6) | 6139 (83.3) | <0.001 | 4008 (86.6) | 7946 (85.4) | 0.057 |
| Spanish/Hispanic | 1976 (14.2) | 745 (11.4) | 1231 (16.7) | 619 (13.4) | 1357 (14.6) | |||
| Insurance (%) | Uninsured | 682 (4.9) | 325 (4.7) | 357 (5.0) | <0.001 | 238 (5.0) | 444 (4.8) | <0.001 |
| Private | 6459 (46.0) | 2886 (42.0) | 3573 (49.7) | 2046 (42.8) | 4413 (47.6) | |||
| Medicaid | 1355 (9.6) | 548 (8.0) | 807 (11.2) | 330 (6.9) | 1025 (11.1) | |||
| Medicare | 5375 (38.3) | 3032 (44.2) | 2343 (32.6) | 2116 (44.2) | 3259 (35.2) | |||
| Other | 176 (1.3) | 73 (1.1) | 103 (1.4) | 52 (1.1) | 124 (1.3) | |||
| Charlson Comorbidity Index (%) | 0 | 10 437 (71.5) | 4825 (68.9) | 5612 (73.9) | <0.001 | 3385 (69.3) | 7052 (72.6) | <0.001 |
| 1 or 2 | 3731 (25.6) | 1949 (27.8) | 1782 (23.5) | 1347 (27.6) | 2384 (24.6) | |||
| 3 | 425 (2.9) | 230 (3.3) | 195 (2.6) | 153 (3.1) | 272 (2.8) | |||
| Median income (%) | <$38 000 | 2548 (17.5) | 1209 (17.4) | 1339 (17.7) | <0.001 | 854 (17.6) | 1694 (17.5) | <0.001 |
| 38 000–47 999 | 3261 (22.5) | 1585 (22.7) | 1676 (22.2) | 1173 (24.1) | 2088 (21.6) | |||
| 48 000–62 999 | 4004 (27.6) | 2016 (28.9) | 1988 (26.3) | 1435 (29.5) | 2569 (26.6) | |||
| ≥63 000 | 4711 (32.4) | 2158 (31.0) | 2553 (33.8) | 1400 (28.8) | 3311 (34.3) | |||
| Education; no HS degree (%) | ≥21.0% | 2961 (20.4) | 1308 (18.8) | 1653 (21.9) | <0.001 | 1007 (20.7) | 1954 (20.2) | 0.741 |
| 13.0%–20.9% | 3558 (24.5) | 1725 (24.7) | 1833 (24.3) | 1199 (24.6) | 2359 (24.4) | |||
| 7.0%–12.9% | 4590 (31.6) | 2283 (32.7) | 2307 (30.5) | 1539 (31.6) | 3051 (31.6) | |||
| <7.0% | 3425 (23.6) | 1660 (23.8) | 1765 (23.4) | 1122 (23.1) | 2303 (23.8) | |||
| Urban/rural (%) | Metro | 12 032 (82.5) | 5698 (81.4) | 6334 (83.5) | 0.003 | 3826 (78.3) | 8206 (84.5) | <0.001 |
| Rural | 642 (4.4) | 336 (4.8) | 306 (4.0) | 268 (5.5) | 374 (3.9) | |||
| Urban | 1919 (13.2) | 970 (13.8) | 949 (12.5) | 791 (16.2) | 1128 (11.6) | |||
| Distance from clinic (%) | >100 miles | 1347 (9.3) | 217 (3.1) | 1130 (14.9) | <0.001 | 218 (4.5) | 1129 (11.7) | <0.001 |
| 10–100 miles | 7430 (51.1) | 2871 (41.1) | 4559 (60.3) | 2101 (43.2) | 5329 (55.1) | |||
| 10 miles or less | 5763 (39.6) | 3891 (55.8) | 1872 (24.8) | 2550 (52.4) | 3213 (33.2) | |||
Note: p‐values were calculated from Chi‐square test with Yate's correction, unless marked with an asterix (*), which were calculated from Kruskal–Wallis rank sum test. p‐values <0.05 were considered significant and were bolded.