Table 5.
Analysis of the risk factors of lung cancer in COPD.
| Risk factors | Studies | Model | OR | Heterogeneity | P difference | |
|---|---|---|---|---|---|---|
| n | (95% CI) | I 2 | P | |||
| Gender | ||||||
| Male | 4 | Random | 0.48 (0.09, 2.66) | 99.50% | 0 | 0.398 |
| Female | 2 | Random | 0.13 (0.00, 4.86) | 99.70% | 0 | 0.268 |
| COPD severity | ||||||
| Mild | 3 | Fixed | 1.79(1.23, 2.60) | 21.90% | 0.278 | 0.002 |
| Moderate | 3 | Fixed | 2.14(1.44, 3.18) | 0 | 0.931 | 0.000 |
| Severe | 2 | Fixed | 1.36(0.80, 2.31) | 0 | 0.419 | 0.251 |
| Very severe | 1 | Fixed | 0.60(0.18, 1.98) | 0 | 0.569 | 0.404 |
| Smoking status | ||||||
| Never smoking | 3 | Fixed | 2.94(2.38, 3.64) | 31.40% | 0.233 | 0.000 |
| Former smoking | 4 | Random | 3.17(1.30, 7.74) | 91.10% | 0 | 0.011 |
| Current smoking | 5 | Random | 3.94(1.28, 12.12) | 95.10% | 0 | 0.017 |