Crude prevalence of irregular and rounded opacities (median scores) among construction workers by duration of exposure, age, and smoking category
| Irregular opacities | Rounded opacities | |||
|---|---|---|---|---|
| n | Profusion category ⩾1/0, n=121 (9.4%) | Profusion category ⩾1/1, n=31 (2.4%) | Profusion category ⩾1/0, n=10 (0.77%) | |
| *Exposure index × duration of exposure. | ||||
| Cumulative exposure index* | ||||
| 0–3.99 | 258 | 19 (7.4%) | 2 (0.8%) | 1 (0.39%) |
| 4–7.99 | 417 | 29 (7.0%) | 5 (1.2%) | 2 (0.48%) |
| 8–14.99 | 335 | 31 (9.3%) | 9 (2.7%) | 1 (0.30%) |
| ⩾15 | 281 | 42 (15%) | 15 (5.3%) | 6 (2.1%) |
| Age at survey | ||||
| 27–35 | 330 | 16 (5%) | 3 (0.9%) | 1 (0.29%) |
| 36–41 | 350 | 28 (8%) | 6 (1.7%) | 3 (0.86%) |
| 42–48 | 315 | 34 (11%) | 10 (3.2%) | 3 (0.95%) |
| ⩾49 | 296 | 43 (15%) | 12 (4.1%) | 3 (1.0%) |
| Pack-years smoked | ||||
| 0–1.9 | 355 | 15 (4.2%) | 3 (0.85%) | 4 (1.1 %) |
| 2–11.9 | 436 | 35 (2.7%) | 8 (1.8%) | 3 (0.69 %) |
| 12–19.9 | 248 | 28 (11%) | 9 (3.6%) | 2 (0.81%) |
| ⩾20 | 252 | 43 (17%) | 11 (4.4%) | 1 (0.40 %) |