Table 4

Gender differences in self-reported non-smoking among cotinine-verified smokers: prevalence ratios (PR), prevalence differences (PD, %) and their 95% CIs

PR (95% CI)PD (95% CI)
Model 1Model 2Model 3Model 3 Model 1Model 2Model 3Model 3
Gender
 MenReferenceReferenceReferenceReferenceReferenceReferenceReferenceReference
 Women4.85 (4.02 to 5.86)*5.13 (4.19 to 6.29)*5.35 (4.34 to 6.60)*6.02 (4.39 to 8.24)*45.4 (38.1 to 52.7)*45.5 (38.0 to 52.9)*44.8 (37.4 to 52.3)*49.2 (37.4 to 61.0)*
Age (per 10 years) 1.18 (0.83 to 1.68)0.95 (0.61 to 1.46)0.79 (0.41 to 1.51) −2.9 (−10.8 to 5.0)−2.2 (−11.5 to 7.0)−3.8 (−26.7 to 19.2)
Age squared 1.00 (0.96 to 1.04)1.02 (0.98 to 1.07)1.04 (0.98 to 1.11) 0.6 (−0.3 to 1.5)0.5 (−0.5 to 1.5)0.9 (−1.3 to 3.1)
Education
 Elementary or less ReferenceReferenceReference ReferenceReferenceReference
 Middle 1.34 (0.84 to 2.13)1.29 (0.80 to 2.07)1.24 (0.66 to 2.33) 1.6 (−4.0 to 7.2)2.9 (−3.2 to 9.1)0.7 (−13.5 to 14.8)
 High 1.92 (1.31 to 2.79)*1.85 (1.25 to 2.74)*1.25 (0.72 to 2.17) 8.0 (2.2 to 13.8)*9.1 (2.7 to 15.4)*−1.9 (−15.9 to 12.1)
 College or higher 2.26 (1.50 to 3.41)*2.19 (1.43 to 3.36)*2.12 (1.18 to 3.79)* 9.7 (3.2 to 16.2)*10.6 (3.5 to 17.8)*11.6 (−5.8 to 29.0)
Occupation
 Non-manual ReferenceReferenceReference ReferenceReferenceReference
 Manual 1.00 (0.77 to 1.31)0.99 (0.76 to 1.31)0.84 (0.55 to 1.28) −0.3 (−5.0 to 4.5)−0.7 (−5.6 to 4.2)−2.6 (−15.7 to 10.5)
 Others 1.03 (0.78 to 1.35)0.99 (0.75 to 1.32)0.71 (0.47 to 1.09) −0.8 (−7.1 to 5.5)−0.5 (−6.9 to 6.0)−11.5 (−25.9 to 2.9)
Current marital status
 No spouse ReferenceReference ReferenceReference
 Married with cohabiting 1.45 (1.11 to 1.88)*1.57 (1.05 to 2.36)* 1.7 (−2.7 to 6.0)6.1 (−5.4 to 17.6)
Cohabiting with parents
 No ReferenceReference ReferenceReference
 Yes 1.37 (1.07 to 1.76)*1.21 (0.79 to 1.86) 1.1 (−3.4 to 5.6)5.8 (−9.3 to 20.8)
Residential area
 Seoul ReferenceReference ReferenceReference
 Other cities 1.23 (0.95 to 1.61)0.95 (0.67 to 1.34) 3.0 (−1.2 to 7.2)−1.8 (−12.8 to 9.1)
 Rural area 1.29 (0.91 to 1.83)0.83 (0.50 to 1.39) 3.4 (−2.2 to 9.0)−8.1 (−21.9 to 5.6)
Secondhand exposure
 None Reference Reference
 <1 h/day 0.85 (0.67 to 1.08) −3.1 (−7.4 to 1.2)
 ≥1 h/day 0.96 (0.75 to 1.22) 0.5 (−3.9 to 4.9)
 Unknown 0.72 (0.39 to 1.34) −1.4 (−11.5 to 8.7)
  • Model 1: adjusted for gender; model 2: adjusted for gender, age, age square, education level, occupation and income; model 3: adjusted for gender, age, age square, education level, occupation, income, marital status, cohabitation with parents, residential area and exposure to secondhand smoke.

  • *p<0.05.

  • The values calculated among subjects without SHS.