Characteristics | Cases n (%) | Controls n (%) |
---|---|---|
No. | 3938 | 1700 |
Age(mean ± SD)* | 64.8 ± 9.6 | 52.2 ± 14.3 |
   ≤65 years | 1803 (45.8) | 1308 (76.9) |
   > 65 years | 2135 (54.2) | 392 (23.1) |
Gender* | Â | Â |
   Male | 3128 (79.4) | 821 (48.3) |
   Female | 810 (20.6) | 879 (51.7) |
Smoking status* | Â | Â |
   Never | 900 (22.8) | 1000 (58.8) |
   Ever | 2951 (74.9) | 655 (38.5) |
   unknown | 87 (2.2) | 45 (2.6) |
Histological type | Â | Â |
   ADC | 1523 (38.7) |  |
   SQC | 1519 (38.6) |  |
   SCLC | 574 (14.6) |  |
   Others | 322 (8.2) |  |