Table 1 Characteristics of social-demographics and major risk factors of NPC cases and controls (%)
Variables | Cases (n = 1845) | Controls (n = 2275) | P* |
|---|---|---|---|
Age, years | 46.11 ± 10.99 | 46.42 ± 11.74 | 0.387 |
Sex | Â | Â | Â |
 Female | 496 (26.88) | 665 (29.23) |  |
 Male | 1373 (73.12) | 1610 (70.77) | 0.096 |
Education | Â | Â | Â |
 High school or lower | 1558 (84.77) | 1554 (68.52) |  |
 College or above | 280 (15.23) | 714 (31.48) | <0.001 |
Living type | Â | Â | Â |
 Block | 671 (37.68) | 1070 (47.79) |  |
 Bungalow | 1110 (62.32) | 1169 (52.21) | < 0.001 |
Cigarette smoking, pack-years | Â | Â | Â |
 Never-smoker | 839 (45.75) | 1190 (52.56) |  |
 <20 | 406 (22.42) | 406 (25.93) | |
 ≥20 | 566 (31.25) | 487 (21.52) | < 0.001 |
Tea | Â | Â | Â |
 Less than monthly | 653 (35.96) | 495 (21.80) |  |
 Monthly | 312 (17.18) | 634 (27.92) |  |
 Weekly or more | 851 (46.86) | 1142 (50.29) | < 0.001 |
Herbal tea | Â | Â | Â |
 Less than monthly | 474 (25.85) | 427 (18.96) |  |
 Monthly | 725 (39.53) | 984 (43.69) |  |
 Weekly or more | 635 (34.62) | 841 (37.34) | < 0.001 |
Slow-cooked soup | Â | Â | Â |
 Less than monthly | 264 (14.43) | 80 (3.55) |  |
 Monthly | 207 (11.32) | 232 (10.30) | |
 Weekly or more | 1358 (74.25) | 1940 (86.15) | < 0.001 |
Salted fish | Â | Â | Â |
 Less than monthly | 1472 (80.22) | 2014 (89.15) |  |
 Monthly | 203 (11.06) | 122 (5.40) | |
 Weekly or more | 160 (8.72) | 123 (5.44) | < 0.001 |
Preserved vegetables | Â | Â | Â |
 Less than monthly | 1318 (71.67) | 1961 (86.81) |  |
 Monthly | 280 (15.23) | 149 (6.60) | |
 Weekly or more | 241 (13.10) | 149 (6.60) | < 0.001 |
Family history of NPC | Â | Â | Â |
 No | 1537 (83.49) | 2075 (94.71) |  |
 Yes | 304 (16.51) | 116 (5.29) | < 0.001 |