Table 2.
Main characteristic of participants in the PLCO cancer screening trial by GL.
| Variables | Q1 (n = 33,732) | Q2 (n = 33,735) | Q3 (n = 33,723) | p value |
|---|---|---|---|---|
| Age (y), mean ± SD | 62.5 (5.3) | 62.6 (5.3) | 62.2 (5.3) | < 0.001 |
| Male (n, %) | 11,540 (34.2%) | 15,654 (46.4%) | 21,885 (64.9%) | < 0.001 |
| Arm (n, %) | ||||
| Screen | 17,263 (51.2%) | 17,144 (50.8%) | 17,124 (50.8%) | 0.52 |
| Control | 16,469 (48.8%) | 16,591 (49.2%) | 16,599 (49.2%) | |
| Smoking (n, %) | < 0.001 | |||
| Never | 16,132 (47.8%) | 16,398 (48.6%) | 15,835 (47.0%) | |
| Current | 3,187 (9.4%) | 2,906 (8.6%) | 3,228 (9.6%) | |
| Former | 14,411 (42.7%) | 14,424 (42.8%) | 14,656 (43.5%) | |
| Missing | 2 (<1%) | 7 (<1%) | 4 (<1%) | |
| Education (n, %) | < 0.001 | |||
| ≤ High school | 14,507 (43.0%) | 13,970 (41.4%) | 14,151 (42.0%) | |
| ≥ Some college | 19,155 (56.8%) | 19,694 (58.4%) | 19,517 (57.9%) | |
| Missing | 70 (0.2%) | 71 (0.2%) | 55 (0.2%) | |
| BMI (n, %) | < 0.001 | |||
| < 25.0 kg/m2 | 11,843 (35.1%) | 11,863 (35.2%) | 10,597 (31.4%) | |
| ≥ 25.0 kg/m2 | 21,436 (63.5%) | 21,449 (63.6%) | 22,668 (67.2%) | |
| Missing | 453 (1.3%) | 423 (1.3%) | 458 (1.4%) | |
| Race (n, %) | < 0.001 | |||
| White, Non-Hispanic | 30,713 (91.1%) | 30,959 (91.8%) | 30,379 (90.1%) | |
| Other | 3,005 (8.9%) | 2,766 (8.2%) | 3,331 (9.9%) | |
| Missing | 14 (<1%) | 10 (<1%) | 13 (<1%) | |
| Drinking (n, %) | < 0.001 | |||
| Never | 3,445 (10.2%) | 3,374 (10.0%) | 3,266 (9.7%) | |
| Former | 4,510 (13.4%) | 4,764 (14.1%) | 5,405 (16.0%) | |
| Current | 24,756 (73.4%) | 24,669 (73.1%) | 24,140 (71.6%) | |
| Missing | 1,021 (3.0%) | 928 (2.8%) | 912 (2.7%) | |
| Total energy intake (kcal/d), mean ± SD | 1123.3 (332.0) | 1633.5 (348.0) | 2423.3 (630.8) | < 0.001 |
GL, glycemic load; PLCO, prostate, lung, colorectal and ovarian; y, year; SD, Standard deviation; BMI, body mass index.