Study population (N=5392)
| Characteristics | All subjects (n=5392) | PP+ (n=1348) | PP− (n=4044) |
| Age at HRCT (years), mean±SD | 66.9±7.2 | 67.2±6.6 | 66.9±7.4 |
| Gender | |||
| Men | 5160 (95.7%) | 1320 (97.9%) | 3840 (95.0%) |
| Women | 232 (4.3%) | 28 (2.1%) | 204 (5.0%) |
| Maximal exposure level to asbestos | |||
| Low | 232 (4.3%) | 22 (1.6%) | 210 (5.2%) |
| Low intermediate | 1318 (24.4%) | 193 (14.3%) | 1125 (27.8%) |
| High intermediate | 2316 (43.0%) | 529 (39.2%) | 1787 (44.2%) |
| High | 1526 (28.3%) | 604 (44.8%) | 922 (22.8%) |
| CEI to asbestos (units-year), mean±SD | 67.7±102.8 | 104.9±122.9 | 55.2±91.9 |
| Time since first exposure (years), mean±SD, min — max | 47.4±8.7 8 — 74 | 48.4±7.6 9 — 74 | 47.1±9.1 8 — 74 |
| Time since last exposure (years), mean±SD, min — max | 15.0±9.9 0 — 62 | 14.3±9.8 0 — 54 | 15.3±9.9 0 — 62 |
| Smoking status | |||
| Smoker | 412 (7.6%) | 99 (7.3%) | 323 (7.7%) |
| Ex-smoker | 3463 (64.2%) | 951 (70.5%) | 2512 (62.1%) |
| Non-smoker | 1517 (28.1%) | 298 (22.1%) | 1219 (30.1%) |
CEI, Cumulative Exposure Index; HRCT, high-resolution CT; PP, pleural plaques.