Table 1. Basic characteristics of the study subjects.
| CRC cases | Controls | P value a | |||
|---|---|---|---|---|---|
| All * | Colon | Rectal | |||
| N | 694 | 336 | 340 | 1641 | |
| Gender(M/F) | 382/312 | 195/141 | 175/165 | 850/791 | 0.151 |
| Age(years) | 62.4 ± 12.3 | 62.9 ± 12.8 | 62.2 ± 11.5 | 57.4 ± 11.6 | <0.001 |
*
As 18 of the CRC cases diagnosed with both colon and rectal cancer, they were excluded in the following stratification analysis for tumor site.
a
The P value for gender was calculated by χ2 test between all the cases and controls, while the P value of the age between the two groups was derived from independent T test.