Table 2.
Demographics and pathologies of case and control groups, n (%)
| Case group | Control group | χ2 | p | |
|---|---|---|---|---|
| Age, years | ||||
| ≤ 50 | 237 (41.5) | 276 (45.3) | 2.847 | 0.241 |
| 51–54 | 138 (24.2) | 151 (24.8) | ||
| 55–59 | 196 (34.3) | 182 (29.9) | ||
| Gender | ||||
| Male | 364 (63.7) | 397 (65.2) | 0.267 | 0.626 |
| Female | 207 (36.3) | 212 (34.8) | ||
| Education | ||||
| Elementary school or less | 278 (48.7) | 208 (34.2) | 27.815 | < 0.001 |
| Middle school | 246 (43.1) | 319 (52.4) | ||
| College and above | 47 (8.2) | 82 (13.5) | ||
| Marital status | ||||
| Married | 550 (96.3) | 575 (94.4) | 2.407 | 0.130 |
| Unmarried and other | 21 (3.7) | 34 (5.6) | ||
| Pathology | ||||
| Adenocarcinoma | 285 (49.9) | – | ||
| Squamous cell carcinoma | 140 (24.5) | – | ||
| Alveolar cell carcinoma | 39 (3.3) | – | ||
| Small cell carcinoma | 47 (8.2) | – | ||
| Large cell carcinoma | 14 (2.5) | – | ||
| Undifferentiated carcinoma | 16 (2.8) | – | ||
| Others | 30 (5.3) | – | ||