Table 1.
Sample description
| Variable | N (%)* |
| Gender | |
| Men | 7338 (74.3) |
| Women | 2538 (25.7) |
| Age | |
| Mean | 64 |
| Median (pct 25 to 75) | 65 (57 to 72) |
| Smoking status* | |
| Never smoker | 1177 (11.9) |
| Ex-smoker | 4636 (46.9) |
| Current smoker | 3965 (40.1) |
| Histological type | |
| Adenocarcinoma | 5138 (52.1) |
| Squamous cell carcinoma | 2394 (24.3) |
| Small cell | 1234 (12.5) |
| Other histological types | 1110 (11.2) |
| Stage at diagnosis | |
| I | 824 (8.3) |
| II | 723 (7.3) |
| III | 2394 (24.2) |
| IV | 4600 (46.6) |
| Small cell limited | 449 (4.5) |
| Small cell extended | 783 (7.9) |
| Other/unknown | 103 (1.1) |
| Main symptoms | |
| Cough | 3344 (33.9) |
| Pain | 2743 (23.8) |
| Dyspnoea | 2638 (26.7) |
| Haemoptysis | 1116 (11.3) |
| Weight loss | 2073 (21.0) |
| Anorexia | 601 (6.1) |
| Asthenia | 983 (10.0) |
| Superior vena cava syndrome | 53 (0.5) |
| Aphonia or voice alterations | 313 (3.2) |
| Number of symptoms at diagnosis | |
| 0 | 3112 (31.5) |
| 1 | 2710 (27.4) |
| 2 | 2077 (21.0) |
| 3 | 1231 (12.5) |
| four or more | 502 (7.6) |
*1% of participants had unknown smoking status.