Independent correlates of exposure to secondhand smoking
| Multivariate logistic regression | |||
| Variable | OR | 95% CI | P value |
| Age (years) | 0.942 | 0.903 to 0.982 | 0.005 |
| Urban | 0.552 | 0.370 to 0.825 | 0.004 |
| Pregnancy phase | – | – | – |
| First trimester | 0.990 | 0.555 to 1.765 | 0.973 |
| Second trimester | 0.504 | 0.275 to 0.921 | 0.026 |
| Third trimester | 0.937 | 0.562 to 1.561 | 0.803 |
| Postnatal | ref | – | – |
| College and above | 0.657 | 0.464 to 0.929 | 0.017 |
| Monthly income≥5000 RMB | 0.809 | 0.582 to 1.126 | 0.209 |
| Having physical comorbidities | 1.801 | 1.172 to 2.769 | 0.007 |
In bold: p<0.05.
1 RMB = 0.144 US dollar