Baseline characteristics of patients in the derivation and validation cohorts. (Figures in the tables are number [%] unless otherwise specified)
| Derivation cohort (n = 2 406 127) | Validation cohort (n = 1 267 151) | |
|---|---|---|
| Sex | ||
| Female | 1 205 833 (50.1) | 634 629 (50.1) |
| Male | 1 200 294 (49.9) | 632 522 (49.9) |
| Mean age (SD), years | 49.7 (14.8) | 49.6 (14.8) |
| Mean Townsend score (SD) | −0.3 (3.4) | −0.1 (3.6) |
| BMI | ||
| BMI recorded prior to study entry | 1 585 199 (65.9) | 860 819 (67.9) |
| Mean BMI in kg/m2 (SD) | 26.4 (4.6) | 26.4 (4.7) |
| Smoking status | ||
| Non smoker | 1 231 186 (51.2) | 644 915 (50.9) |
| Ex-smoker | 417 269 (17.3) | 223 718 (17.7) |
| Current smoker, amount not recorded | 73 325 (3.0) | 40 439 (3.2) |
| Light smoker (<10/day) | 153 421 (6.4) | 82 973 (6.5) |
| Moderate smoker (10–19/day) | 187 856 (7.8) | 100 354 (7.9) |
| Heavy smoker (≥20/day) | 141 040 (5.9) | 77 679 (6.1) |
| Smoking status not recorded | 202 030 (8.4) | 97 073 (7.7) |
| Medical history | ||
| Family history of lung cancer | 13 378 (0.6) | 8078 (0.6) |
| Prior cancer (apart from lung cancer) | 48 548 (2.0) | 25 547 (2.0) |
| Asthma | 182 800 (7.6) | 99 417 (7.8) |
| Chronic obstructive airways disease | 37 191 (1.5) | 21 458 (1.7) |
| Pneumonia | 31 840 (1.3) | 17 238 (1.4) |
| Asbestos exposure | 1649 (0.1) | 928 (0.1) |
| Current symptoms and symptoms in the preceding year | ||
| Current haemoptysis | 13 980 (0.6) | 8010 (0.6) |
| Current appetite loss | 11 853 (0.5) | 6303 (0.5) |
| Current weight-loss symptom | 30 937 (1.3) | 17 355 (1.4) |
| Cough in last year | 55 434 (2.3) | 30 298 (2.4) |
| Dyspnoea in last year | 11 549 (0.5) | 5887 (0.5) |
| Tiredness in last year | 22 779 (0.9) | 12 854 (1.0) |
| Hoarseness | 1748 (0.1) | 966 (0.1) |
| Haemoglobin recorded in the last year | 351 100 (14.6) | 189 945 (15.0) |
| Haemoglobin <11 g/dl in the last year | 13 980 (0.6) | 8010 (0.6) |
SD = standard deviation.