Table 1. Demographics and baseline characteristics of study subjects.
| Characteristics | Cases (513) | Controls (576) | P- value |
|---|---|---|---|
| Age(years)a mean ± s.d. | 60.14 ± 11.29 | 57.16 ± 11.25 | < 0.001 |
| Gender | 0.805 | ||
| Male | 302 (58.87) | 334 (57.99) | |
| Female | 211 (41.13) | 242 (42.01) | |
| BMI(kg/m2)a mean ± s.d. | 23.26 ± 3.35 | 24.27 ± 4.14 | < 0.001 |
| Occupation | < 0.001 | ||
| Mental worker | 199 (38.79) | 156 (27.08) | |
| Physical worker | 224 (43.66) | 266 (46.18) | 0.003 |
| Combined | 86 (16.76) | 154 (26.74) | |
| Education | 0.424 | ||
| Illiterate | 134 (26.12) | 168 (29.17) | |
| Primary school | 151 (29.43) | 174 (30.21) | |
| high school or above | 204 (39.77) | 210 (36.46) | |
| Family history of cancer | 0.168 | ||
| No | 408 (79.53) | 484 (84.03) | |
| Yes | 94 (18.32) | 89 (15.45) | |
| Tumor site | |||
| Colon | 168 (32.75) | ||
| Rectal | 312 (60.82) | ||
| Cecum | 30 (5.85) |
aAge and BMI are continuous variables, the others are categorical variables.
Missing data: tumor site, 3.