Table 2: Adjusted odds ratios and their 95% confidence intervals (CIs) for the association between sociodemographic and smoking-related variables with overall SHS exposure.

FactorOverall SHS exposure OR 95% CI
Exposed
Not exposed

Age (in years)
 <13913781.00Reference
 13–1641512421.431.24–1.61
 >162957891.611.14–2.25
Sex
 Female37711861.00Reference
 Male42412231.140.92–1.28
School grade
 Intermediate39813451.00Reference
 Secondary40310641.331.09–1.50
Father’s education
 No formal education491081.00Reference
 Less than university37710200.760.67–0.98
 University or higher37512810.650.50–0.87
Mother’s education
 No formal education671621.00Reference
 Less than university38912060.820.66–1.17
 University or higher34510410.850.71–1.20
Family structure
 One or both parents75923601.00Reference
 Neither42492.661.75–4.05
Smoking status
 Nonsmoker36518111.00Reference
 Smoker or former smoker4365983.663.06–4.27
Parents smoking
 Nonsmokers40820171.00Reference
 One or both are smokers3933924.954.15–5.90
Close friends smoking
 No26515521.00Reference
 Some of them smoke5368573.713.09–4.33
Knowledge about harmful effects of smoking
 No59317311.00Reference
 Yes2086780.890.75–1.07
Belief in harmful effects of SHS
 No3117911.00Reference
 Yes49016180.710.65–0.90

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