Table 3: Adjusted odds ratios and their 95% confidence intervals (CIs) for the association between sociodemographic and smoking-related variables and SHS exposure at home.

FactorSHS exposure at home OR 95% CI
Exposed
Not exposed

Age (in years)
 <131283411.00Reference
 13–1655511021.330.96–1.49
 >163667181.360.98–1.52
Sex
 Female52010431.00Reference
 Male52911180.950.82–1.10
School grade
 Intermediate54411991.00Reference
 Secondary5059621.160.99–1.34
Father’s education
 No formal education64931.00Reference
 Less than university4979000.750.66–0.86
 University or higher48811680.530.42–0.69
Mother’s education
 No formal education841451.00Reference
 Less than university52710680.950.74–1.15
 University or higher4389480.840.62–1.11
Family structure
 One or both parents100221171.00Reference
 Neither47442.261.48–3.42
Smoking status
 Nonsmoker53116451.00Reference
 Smoker or former smoker5185163.112.66–3.63
Parents smoking
 Nonsmokers53918861.00Reference
 One or both are smokers5102756.495.44– 7.73
Close friends smoking
 No41913981.00Reference
 Some of them smoke6307632.752.36–3.20
Knowledge about harmful effects of smoking
 No78015441.00Reference
 Yes2696170.870.73–1.02
Belief in harmful effects of SHS
 No3937091.00Reference
 Yes65614520.750.69–0.95

Each variable is adjusted by the other variables in the table.