Table 4:
Coffee consumption and lung cancer in the overall groups and smoking status subgroups, as well as logistic regression analyses of the association (N=500).
| Lung cancer | Odds ratio (OR) | p-value‡ | ||
|---|---|---|---|---|
| Yes [n=250] n (%)† | No [n=250] n (%)† | |||
| Overall | ||||
| Coffee (+) | 200 (80.0) | 164 (65.6) | 2.10 | <0.001 |
| Coffee (–) | 50 (20.0) | 86 (34.4) | ||
| Subgroups: | ||||
| Non-smokers | ||||
| Coffee (+) | 24 (64.9) | 125 (61.9) | 1.14 | 0.731 |
| Coffee (–) | 13 (35.1) | 77 (38.1) | ||
| Smokers | ||||
| Coffee (+) | 176 (82.6) | 39 (81.2) | 1.10 | 0.821 |
| Coffee (–) | 37 (17.4) | 9 (18.8) | ||
| M-H adjusted OR | 1.12 | |||
| M-H test of homogeneity (p-value) | 0.949 | |||
| Magnitude of confounding (%)* | 87.5 | |||
| Univariable analysis | Multivariable analysis | |||||
|---|---|---|---|---|---|---|
| cOR | 95% CI | p-value | aOR | 95% CI | p-value | |
| Coffee | ||||||
| <1 cup/day | Reference | Reference | ||||
| ≥1 cup/day | 2.10 | 1.40, 3.15 | <0.001 | 1.12 | 0.65, 1.92 | 0.683 |
| Smoking | ||||||
| No | - | Reference | ||||
| Yes | - | 23.72 | 14.69, 38.31 | <0.001 | ||
Coffee (+), ≥ 1 cup a day; Coffee (–), <1 cup a day
CI, confidence interval; M-H adjusted OR, Mantel-Haenszel adjusted OR;
M-H test of homogeneity, Mantel-Haenszel test of homogeneity of stratum-specific ORs;
cOR, crude odds ratio; aOR, adjusted odds ratio
† Percentage by column
‡ Chi-square test
* Calculated by [(ORcrude – ORadjusted) / ORadjusted]×100%