Table 4. Schema of significant lifestyle factors on the risks of colorectal cancer (CRC) and adenomas/polyps (AP) per case-control or cohort-control study designs and ethnic subgroups.
| Number of studies (n Case/n Control) |
Alcohol | Smoking | |
|---|---|---|---|
| CRC | AP | AP | |
| Case/Control | ES:NS RR:NS |
8 studies (2,243/2,482) ES = 0.37*** 7 studies (1,926/2,097) RR, high level = 1.09** |
2 studies (896/976) ES = 0.1* 11 studies (2,314/3,171) RR, high level = 1.44**** |
| Subgroups | |||
| European | ES:NS 4 studies (230/425) RR, low level = 0.82** |
ES:NS 2 studies (71/104) RR, low level = 0.73* |
4 studies (955/1,220) RR, low level = 0.82**** |
| Caucasian | ES:NS | 3 studies (1,423/1,621) ES = 0.12*** 3 studies (704/739) RR, high level = 1.12** |
2 studies (896/976) ES = 0.1* 3 studies (839/1,033) RR, high level = 1.64**** |
| East Asian | – | – | 4 studies (520/918) RR, high level = 1.23**** |
| Cohort/Control | ES:NS RR:NS |
ES:NS RR:NS |
5 studies (2,986/4,553) ES = 0.17**** 7 studies (2,217/4,197) RR, high level = 1.11* |
| Subgroups | – | – | |
| Caucasian | – | – | 5 studies (2,986/4,553) ES = 0.17**** RR:NS |
Notes: ES: Effect size; RR: Risk ratio; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001; NS: Not significant; –: No data; Blue font denotes relative risk related parameters.