TABLE 1.
Baseline Characteristics of Study Cohort Stratified by Treatment and Observation Groups
| Group |
||||
|---|---|---|---|---|
| All N = 1800 |
Observation N = 315 |
Treatment N = 1485 |
P a | |
| Mean age at diagnosis (SD), y | 73.6 (8.2) | 74.1 (8.6) | 73.5 (8.2) | .29 |
| Male sex, no. (%) | 1418 (78.8) | 248 (78.7) | 1170 (78.8) | .98 |
| White race/ethnicity, no. (%) | 1757 (97.6) | 312 (99.1) | 1445 (97.3) | .07 |
| Health system, no. (%) | ||||
| Geisinger | 938 (52.1) | 243 (77.1) | 695 (46.8) | <.01 |
| Kaiser Permanente Northwest | 862 (47.9) | 72 (22.9) | 790 (53.2) | |
| Obese BMI, no. (%) | 594 (33.0) | 80 (25.4) | 514 (34.6) | <.01 |
| Smoking status, no. (%) | ||||
| Current/former smoker | 1322 (73.4) | 219 (69.5) | 1103 (74.3) | <.01 |
| Never smoker | 435 (24.2) | 71 (22.5) | 364 (24.5) | |
| Never assessed/unknown if ever smoked | 43 (2.4) | 25 (7.9) | 18 (1.2) | |
| Multiple chronic conditions at baseline: yes, no. (%) | 1204 (66.9) | 159 (50.5) | 1045 (70.4) | <.01 |
| AJCC stage of disease/grade, no. (%) | ||||
| 0A/low grade | 921 (51.2) | 216 (68.6) | 705 (47.5) | <.01 |
| 0A/high grade | 318 (17.7) | 22 (7.0) | 296 (19.9) | |
| 0IS/high grade | 92 (5.1) | 16 (5.1) | 76 (5.1) | |
| I/high grade | 451 (25.1) | 60 (19.0) | 391 (26.3) | |
| Unknown | 18 (1.0) | 1 (0.32) | 17 (1.1) | |
| Alive status within 10 y of index date, no. (%) | 1075 (59.7) | 143 (45.4) | 932 (62.8) | <.01 |
Abbreviations: AJCC, American Joint Committee on Cancer; BMI, body mass index; SD, standard deviation.
a
Comparing the treatment and observation groups.