Table 1.
Baseline Demographics and Clinical Characteristics of the Cohort
| Patient Demographics and Clinical Characteristics | No. of Patients (N = 10,773) | Any CSF v No CSF (n = 5,266; 48.9%) |
First-Cycle CSF v No CSF (n = 2,056; 19.1%) |
||
|---|---|---|---|---|---|
| No. of Patients | % | No. of Patients | % | ||
| Age at diagnosis, years | |||||
| 65-69 | 4,030 | 2,009 | 49.8* | 859 | 21.3* |
| 70-74 | 3,696 | 1,844 | 49.9 | 675 | 18.3 |
| 75-79 | 2,193 | 1,073 | 48.9 | 400 | 18.2 |
| ≥ 80 | 854 | 340 | 39.8 | 122 | 14.3 |
| Race | |||||
| White | 9,322 | 4,594 | 49.3* | 1,789 | 19.2 |
| Black | 828 | 357 | 43.1 | 147 | 17.8 |
| Hispanic | 143 | 57 | 39.9 | 21 | 14.7 |
| Missing or other | 480 | 258 | 53.7 | 102 | 21.2 |
| Residence | |||||
| Urban | 9,802 | 4,864 | 49.6* | 1,904 | 19.4* |
| Rural | 971 | 402 | 41.4 | 152 | 15.6 |
| Marital status | |||||
| Married | 5,731 | 2,864 | 50.0* | 1,130 | 19.7 |
| Unmarried | 4,733 | 2,247 | 47.5 | 862 | 18.2 |
| Unknown | 309 | 155 | 50.2 | 64 | 20.7 |
| Socioeconomic status | |||||
| Lowest (first) quintile | 1,358 | 634 | 46.7* | 237 | 17.4* |
| Second quintile | 2,067 | 961 | 46.5 | 339 | 16.4 |
| Third quintile | 2,371 | 1,169 | 49.3 | 467 | 19.7 |
| Fourth quintile | 2,413 | 1,190 | 49.3 | 467 | 19.4 |
| Highest (fifth) quintile | 2,559 | 1,308 | 51.1 | 545 | 21.3 |
| Comorbidity score | |||||
| 0 | 8,689 | 4,284 | 49.3* | 1,657 | 19.1 |
| 1 | 1,604 | 772 | 48.1 | 306 | 19.1 |
| > 1 | 480 | 210 | 43.7 | 93 | 19.4 |
| Tumor stage | |||||
| I | 1,966 | 864 | 43.9* | 294 | 15.0* |
| II | 6,683 | 3,190 | 47.7 | 1,133 | 17.0 |
| III | 2,124 | 1,212 | 57.1 | 629 | 29.6 |
| Tumor grade | |||||
| High | 4,880 | 2,425 | 49.7 | 923 | 18.9 |
| Low | 5,061 | 2,457 | 48.5 | 993 | 19.6 |
| Unknown | 832 | 384 | 46.1 | 140 | 16.8 |
| Chemotherapy type | |||||
| Taxane + anthracycline | 3,433 | 2,338 | 68.1* | 1,254 | 36.5* |
| Anthracycline | 3,436 | 1,751 | 50.9 | 594 | 17.3 |
| Taxane | 558 | 185 | 33.1 | 75 | 13.4 |
| Other | 3,346 | 992 | 30.0 | 133 | 3.9 |
| Chemotherapy duration, weeks | |||||
| 1-13 | 3,492 | 1,518 | 43.5* | 605 | 17.3* |
| 14-26 | 5,331 | 2,668 | 50.1 | 1,038 | 19.5 |
| > 26 | 1,950 | 1,080 | 55.4 | 413 | 21.2 |
| Hormone-receptor status | |||||
| Negative | 3,016 | 1,474 | 48.9 | 603 | 20.0* |
| Positive | 6,424 | 3,174 | 49.4 | 1,245 | 19.4 |
| Missing | 1,333 | 618 | 46.4 | 208 | 15.6 |
| Oncologist training | |||||
| Non–United States | 2,860 | 1,604 | 56.1* | 647 | 22.6* |
| United States | 7,561 | 3,503 | 46.3 | 1,353 | 17.9 |
| Oncologist degree | |||||
| DO | 444 | 190 | 42.8* | 83 | 18.7 |
| MD | 9,977 | 4,917 | 49.3 | 1,917 | 19.2 |
| Specialty | |||||
| Nononcologist | 787 | 357 | 45.4* | 142 | 18.0 |
| Oncologist | 9,634 | 4,750 | 49.3 | 1,858 | 19.3 |
| Oncologist sex | |||||
| Male | 8,250 | 3,971 | 48.1* | 1,536 | 18.6* |
| Female | 2,100 | 1,100 | 52.4 | 451 | 21.5 |
| Oncologist year of graduation | |||||
| 1990s | 1,376 | 774 | 56.2* | 182 | 14.8* |
| 1980s | 3,580 | 1,835 | 51.3 | 731 | 17.5 |
| 1970s | 4,168 | 1,903 | 45.7 | 735 | 20.5 |
| 1960s | 1,226 | 559 | 45.6 | 339 | 24.6 |
| Oncologist practice setting | |||||
| Non–private practice | 2,154 | 1,086 | 50.4 | 430 | 20.0 |
| Private practice | 8,196 | 3,985 | 48.6 | 1,557 | 19.0 |
| Volume | |||||
| 1-9 cases | 5,584 | 2,732 | 48.9 | 1,083 | 19.4 |
| ≥ 10 cases | 4,920 | 2,421 | 49.2 | 934 | 19.0 |
Abbreviations: CSF, colony-stimulating factor; DO, Doctor of Osteopathic Medicine; MD, Doctor of Medicine.
*
P ≤ .05 (χ2 test).