Table 2. Significant risk factors for medium-term SHS exposure in weighted multiple logistic regression.

Characteristic variables	Adjusted OR (95% CI)	P value
Age group: ≥60 vs. 40–59 years	0.34 (0.13–0.87)	0.03*
Ethnicity: black vs. white	1.66 (0.70–3.94)	0.24
Ethnicity: Mexican-American and other vs. white	0.30 (0.11–0.82)	0.02*
Family income-to-poverty ratio grading: high vs. middle	0.31 (0.15–0.66)	<0.01*
Family income-to-poverty ratio grading: low vs. middle	1.69 (0.68–4.23)	0.25
Smoking history: former vs. never	3.77 (1.29–10.99)	0.02*
Self-reported SHS at home: yes vs. no	23.30 (4.90–110.94)	<0.01*

Data obtained from the National Health and Nutrition Examination Survey (2007–2012), National Center for Health Statistics. *, statistical significance of the coefficients at the P<0.05 level in the model. CI, confidence interval; OR, odds ratio; SHS, secondhand smoke