Table 1. Baseline Patient Characteristics According to TTI.
| Characteristic | Median (IQR) TTI, days | No. (%) of Patients by TTI in Days | Total (N = 51,655) | P | |||
|---|---|---|---|---|---|---|---|
|
| |||||||
| 0-30 (n = 30,744; 60%) | 31-60 (n = 15,636; 30%) | 61-90 (n = 3,648; 7%) | >90 (n = 1,627; 3%) | ||||
| Age, years | < .001 | ||||||
| ≤ 30 | 24 (13-38) | 177 (< 1) | 70 (< 1) | 13 (< 1) | 13 (1) | 273 | |
| 31-40 | 23 (9-40) | 799 (3) | 371 (2) | 76 (2) | 35 (2) | 1,281 | |
| 41-50 | 26 (12-42) | 4,787 (16) | 2,511 (16) | 596 (16) | 259 (16) | 8,153 | |
| 51-60 | 27 (13-42) | 8,818 (28) | 4,817 (31) | 1,214 (33) | 558 (34) | 15,407 | |
| 61-70 | 26 (13-41) | 8,377 (27) | 4,300 (28) | 996 (27) | 449 (28) | 14,122 | |
| > 70 | 24 (10-39) | 7,786 (25) | 3,567 (22) | 753 (21) | 313 (19) | 12,419 | |
|
| |||||||
| Sex | .967 | ||||||
| Male | 26 (12-41) | 23,344 (76) | 11,884 (76) | 2,765 (76) | 1,243 (76) | 39,236 | |
| Female | 26 (12-41) | 7,400 (24) | 3,752 (24) | 883 (24) | 384 (24) | 12,419 | |
|
| |||||||
| Race | < .001 | ||||||
| White | 25 (12-40) | 26,692 (87) | 13,257 (85) | 2,929 (80) | 1,266 (78) | 44,144 | |
| African American | 28 (14-47) | 3,128 (10) | 1,901 (12) | 595 (16) | 305 (19) | 5,929 | |
| Asian | 26 (12-42) | 385 (1) | 199 (1) | 56 (2) | 17 (1) | 657 | |
| Other | 26 (13-41) | 539 (2) | 279 (2) | 68 (2) | 39 (2) | 925 | |
|
| |||||||
| Hispanic ethnicity | < .001 | ||||||
| Non-Hispanic | 26 (12-41) | 26,805 (87) | 13,638 (87) | 3,202 (88) | 1,378 (85) | 45,023 | |
| Hispanic | 29 (13-49) | 964 (3) | 595 (4) | 178 (5) | 123 (7) | 1,860 | |
| Other | 24 (12-39) | 2,975 (10) | 1,403 (9) | 268 (7) | 126 (8) | 4,772 | |
|
| |||||||
| Insurance status | < .001 | ||||||
| Private insurance | 25 (12-40) | 13,262 (43) | 6,686 (43) | 1,423 (39) | 568 (35) | 21,939 | |
| Medicare | 25 (11-39) | 12,232 (40) | 5,659 (36) | 1,214 (33) | 574 (35) | 19,679 | |
| Uninsured | 28 (14-45) | 1,427 (5) | 863 (6) | 245 (7) | 112 (7) | 2,647 | |
| Medicaid | 29 (15-49) | 2,234 (7) | 1,420 (9) | 454 (12) | 236 (15) | 4,344 | |
| Other government | 32 (17-49) | 427 (1) | 307 (2) | 103 (3) | 48 (3) | 885 | |
| Unknown | 28 (14-48) | 1,162 (4) | 701 (4) | 209 (6) | 89 (5) | 2161 | |
|
| |||||||
| Facility type | < .001 | ||||||
| Community | 22 (9-39) | 3,396 (11) | 1,501 (10) | 309 (9) | 158 (9) | 5,364 | |
| Comprehensive Community | 23 (10-38) | 16,049 (52) | 6,979 (45) | 1,476 (40) | 669 (41) | 25,173 | |
| Academic | 28 (15-45) | 10,719 (35) | 6,949 (44) | 1,816 (50) | 775 (48) | 20,259 | |
| Other | 20 (6-35) | 580 (2) | 207 (1) | 47 (1) | 25 (2) | 859 | |
|
| |||||||
| Distance from treatment facility, miles | < .001 | ||||||
| ≤ 10 | 26 (12-41) | 16,313 (53) | 8,043 (51) | 1,920 (53) | 888 (55) | 27,164 | |
| 10-20 | 25 (11-40) | 5,772 (19) | 2,808 (18) | 596 (16) | 253 (16) | 9,429 | |
| 21-50 | 26 (13-41) | 5,502 (18) | 2,799 (18) | 629 (17) | 247 (15) | 9,177 | |
| 51-100 | 28 (14-43) | 1,954 (6) | 1,131 (7) | 297 (8) | 140 (8) | 3,522 | |
| > 100 | 30 (12-41) | 1,203 (4) | 855 (6) | 206 (6) | 99 (6) | 2,363 | |
|
| |||||||
| Charlson/Deyo comorbidity score | .131 | ||||||
| 0 | 26 (13-41) | 25,416 (83) | 13,038 (83) | 3,051 (84) | 1321 (81) | 4,2826 | |
| 1 | 25 (12-41) | 4,199 (14) | 2,043 (13) | 469 (13) | 249 (15) | 6,960 | |
| ≥ 2 | 24 (12-40) | 1,129 (3) | 555 (4) | 128 (3) | 57 (4) | 1,869 | |
|
| |||||||
| Cancer primary site | < .001 | ||||||
| Oral tongue | 28 (14-44) | 8,325 (27) | 4,896 (31) | 1,236 (34) | 554 (34) | 15,011 | |
| Oropharynx, tonsil | 26 (9-41) | 5,528 (18) | 2,735 (18) | 660 (18) | 269 (17) | 9,192 | |
| Oropharynx, nontonsil | 30 (15-44) | 1,172 (4) | 737 (5) | 209 (6) | 77 (4) | 2,195 | |
| Larynx | 23 (9-38) | 13,743 (45) | 5,940 (38) | 1,217 (33) | 580 (36) | 21,480 | |
| Hypopharynx | 29 (18-45) | 1,976 (6) | 1,328 (8) | 326 (9) | 147 (9) | 3,777 | |
|
| |||||||
| Overall AJCC stage group | < .001 | ||||||
| I | 20 (0-34) | 8,855 (29) | 2,943 (19) | 539 (15) | 300 (19) | 12,637 | |
| II | 26 (12-39) | 4,950 (16) | 2,470 (16) | 479 (13) | 193 (12) | 8,092 | |
| Ill | 27 (14-42) | 6,029 (20) | 3,529 (22) | 884 (24) | 349 (21) | 10,791 | |
| IV | 28 (15-45) | 10,910 (35) | 6,694 (43) | 1,746 (48) | 785 (48) | 20,135 | |
|
| |||||||
| Treatment | < .001 | ||||||
| Surgery alone | 17 (0-34) | 6,858 (22) | 2,125 (14) | 442 (12) | 244 (15) | 9,669 | |
| RT alone | 31 (21-45) | 5,929 (19) | 4,402 (28) | 1,005 (28) | 515 (32) | 11,851 | |
| CRT | 34 (22-49) | 6,607 (21) | 6,640 (42) | 1,689 (46) | 670 (41) | 15,606 | |
| Adjuvant RT | 8 (0-26) | 7,069 (23) | 1,366 (9) | 267 (7) | 119 (7) | 8,821 | |
| Adjuvant CRT | 13 (0-27) | 3,552 (12) | 694 (4) | 151 (4) | 42 (2) | 4,439 | |
| Adjuvant chemotherapy | 14 (0-31) | 174 (1) | 42 (< 1) | 12 (< 1) | 5 (< 1) | 233 | |
| Preoperative RT | 30 (18-43) | 114 (< 1) | 85 (< 1) | 17 (< 1) | 9 (< 1) | 225 | |
| Preoperative CRT | 29 (18-43) | 381 (1) | 264 (1) | 62 (2) | 21 (1) | 728 | |
| Preoperative chemotherapy | 18 (10-34) | 60 (< 1) | 18 (< 1) | 3 (< 1) | 2 (< 1) | 83 | |
|
| |||||||
| Treatment year | < .001 | ||||||
| 2003 | 25 (12-40) | 10,639 (35) | 4,870 (31) | 1,186 (33) | 564 (35) | 17,259 | |
| 2004 | 26 (13-41) | 10,108 (33) | 5,314 (34) | 1,177 (32) | 489 (30) | 17,088 | |
| 2005 | 27 (13-42) | 9,997 (32) | 5,452 (35) | 1,285 (35) | 574 (35) | 17,308 | |
|
| |||||||
| Transition to academic facility | < .001 | ||||||
| Yes | 34 (21-51) | 4,123 (13) | 3,932 (25) | 1,147 (31) | 487 (30) | 9,689 | |
| No | 24 (10-38) | 26,621 (87) | 11,704 (75) | 2,501 (69) | 1,140 (70) | 41,966 | |
|
| |||||||
| Zip-code level education, % | < .001 | ||||||
| ≥ 29 | 27 (13-43) | 5,534 (18) | 3,015 (19) | 797 (22) | 420 (26) | 9,766 | |
| 20-28.9 | 26 (13-41) | 7,311 (24) | 3,794 (24) | 891 (24) | 418 (26) | 12,414 | |
| 14-19.9 | 26 (12-41) | 7,065 (23) | 3,558 (23) | 776 (21) | 337 (21) | 11,736 | |
| < 14 | 25 (12-40) | 9,127 (30) | 4,459 (29) | 982 (27) | 359 (22) | 14,927 | |
| Unknown | 24 (11-41) | 1,707 (5) | 810 (5) | 202 (6) | 93 (5) | 2,812 | |
|
| |||||||
| Zip-code level income, $ | < .001 | ||||||
| < 30,000 | 26 (13-43) | 4,782 (16) | 2,586 (17) | 670 (18) | 332 (20) | 8,370 | |
| 30,000-35,000 | 26 (13-41) | 5,867 (19) | 2,967 (19) | 627 (17) | 345 (21) | 9,806 | |
| 35,000-45,999 | 26 (12-41) | 8,398 (27) | 4,152 (26) | 971 (27) | 411 (25) | 13,932 | |
| ≥ 46,000 | 26 (12-41) | 9,992 (33) | 5,121 (33) | 1,178 (32) | 446 (28) | 16,737 | |
| Unknown | 24 (12-41) | 1,705 (5) | 810 (5) | 202 (6) | 93 (6) | 2,810 | |
NOTE. Characteristics were compared by using the χ2 test. All covariates were analyzed as categoric variables.
Abbreviations: AJCC, American Joint Committee on Cancer; CRT, chemoradiation; RT, radiation therapy; TTI, time to initiation.