Table 1.
Patient Characteristics
| Variable Name | Overall (N = 7,287) | RS Testing | P | |
|---|---|---|---|---|
| No (n = 5,678) | Yes (n = 1,609) | |||
| Age at diagnosis, mean (SD), years | 71.6 (11.6) | 73.4 (11.2) | 65.3 (10.8) | < .001 |
| Age category, years | ||||
| < 55 | 733 (10) | 447 (7.9) | 286 (18) | < .001 |
| 55-64 | 762 (10) | 445 (7.8) | 317 (20) | |
| 65-74 | 2,526 (35) | 1,831 (32) | 695 (43) | |
| 75-84 | 2,479 (34) | 2,179 (38) | 300 (19) | |
| ≥ 85 | 787 (11) | 776 (14) | 11 (0.7) | |
| Race/ethnicity | ||||
| White, non-Hispanic | 5,896 (81) | 4,572 (81) | 1,324 (82) | .22 |
| Nonwhite or Hispanic | 612 (8.4) | 481 (8.5) | 131 (8.1) | |
| Race/ethnicity missing | 779 (11) | 625 (11) | 154 (9.6) | |
| Payer | ||||
| Medicare | 5,407 (74) | 4,453 (78) | 954 (59) | < .001 |
| Independence | 1,880 (26) | 1,225 (22) | 655 (41) | |
| Cancer stage | ||||
| I | 5,542 (76) | 4,280 (75) | 1,262 (78) | < .001 |
| II | 1,550 (21) | 1,224 (22) | 326 (20) | |
| III | 87 (1.2) | 83 (1.5) | 4 (0.2) | |
| Missing | 108 (1.5) | 91 (1.6) | 17 (1.1) | |
| Tumor grade | ||||
| 1 | 2,018 (28) | 1,622 (29) | 396 (25) | < .001 |
| 2 | 3,190 (44) | 2,331 (41) | 859 (53) | |
| 3 | 1,628 (22) | 1,350 (24) | 278 (17) | |
| 4 | 41 (0.6) | 39 (0.7) | 2 (0.1) | |
| Missing | 410 (5.6) | 336 (5.9) | 74 (4.6) | |
| Tumor size, cm | ||||
| < 1 | 2,261 (31) | 1,904 (34) | 357 (22) | < .001 |
| 1-2 | 3,919 (54) | 2,813 (50) | 1,106 (69) | |
| > 2 | 797 (11) | 680 (12) | 117 (7.3) | |
| Missing | 310 (4.3) | 281 (4.9) | 29 (1.8) | |
| Diagnosis year | ||||
| 2007 | 1,876 (26) | 1,573 (28) | 303 (19) | < .001 |
| 2008 | 1,831 (25) | 1,421 (25) | 410 (25) | |
| 2009 | 1,819 (25) | 1,408 (25) | 411 (26) | |
| 2010 | 1,761 (24) | 1,276 (22) | 485 (30) | |
| Prior year health care spending, $ | ||||
| Mean (SD) | 6,028 (12,400) | 6,261 (12,993) | 5,205 (9,993) | .003 |
| Median (IQR) | 2,244 (4632) | 2,288 (4,784) | 2,144 (4,192) | .25 |
| Elixhauser22 comorbidity count | ||||
| 0 | 1,388 (19) | 989 (17) | 399 (25) | < .001 |
| 1-3 | 4,087 (56) | 3,157 (56) | 930 (58) | |
| ≥ 4 | 1,812 (25) | 1,532 (27) | 280 (17) | |
NOTE. Data are presented as No. (% of the column’s total patients) unless otherwise specified.
Abbreviations: RS, 21-gene recurrence score assay; IQR, interquartile range.