Table 1.
Background characteristics of cases and their controls
| Controls n (%) | Cases n (%) | χ2 MH | P | |
| Age (yr) | ||||
| <50 | 10 (4.53) | 8 (4.19) | ||
| 50-59 | 57(25.79) | 60 (31.41) | ||
| 60-69 | 98 (44.34) | 80 (41.88) | ||
| > 70 | 56 (25.34) | 43 (22.52) | 0.91 | 0.341 |
| Total | 221 | 191 | ||
| Income (yuan/year per person) | ||||
| Ten years before | 2097 | 3040 | < 0.01 | |
| Recent years | 3629 | 4746 | < 0.01 | |
| Drinking status | ||||
| Non-drinker | 96 (43.44) | 94 (49.21) | ||
| Drinker | 125 (56.56) | 97 (50.79) | 1.38 | 0.24 |
| Smoking status | ||||
| Non-smoker | 70 (31.67) | 58 (30.37) | ||
| Smoker | 151 (68.33) | 133 (69.63) | 0.78 | 0.08 |