Description of the study cohort
| Variable | |
| Patients n | 323 |
| Sex | |
| Male | 63 (19.5) |
| Female | 260 (80.5) |
| Age years | |
| Mean | 69 |
| Median | 70 |
| Percentile 25–75 | 61–78 |
| Minimum | 35 |
| Maximum | 94 |
| Education (completed studies) | |
| No formal studies | 143 (44.3) |
| Primary studies | 120 (37.2) |
| Secondary studies | 29 (9.0) |
| University degree | 26 (8.0) |
| Unknown | 5 (1.5) |
| Histological type | |
| Squamous cell carcinoma | 30 (9.3) |
| Adenocarcinoma | 253 (78.3) |
| Small cell lung cancer | 19 (5.9) |
| Large cell lung cancer | 8 (2.5) |
| Other types | 12 (3.7) |
| Unknown | 1 (0.3) |
| Stage at diagnosis# | |
| I | 35 (14.3) |
| II | 14 (5.7) |
| IIIA | 30 (12.2) |
| IIIB | 18 (7.3) |
| IV | 148 (60.4) |
| Small cell lung cancer | 19 |
| Unknown | 59 |
| Residential radon exposure Bq·m−3 | |
| Mean | 271 |
| Median | 182 |
| Percentile 25–75 | 103.5–333 |
| Minimum | 11 |
| Maximum | 2350 |
| Unknown | 38 (11.7) |
| Years living with a smoker | |
| <20 | 180 (55.7) |
| ≥20 | 143 (44.3) |
| Years living in the measured dwelling | |
| Mean | 31.4 |
| Median | 30 |
| Percentile 25–75 | 14–44 |
Data are presented as n (%) unless otherwise stated. #: percentages calculated excluding unknown stages and small cell lung cancer.