Characteristic Total Gender Male (reference) Female Race/Ethnicity Non-Hispanic White (reference) Non-Hispanic Black Mexican American Other Hispanic Other Race (including multi-racial) Country of Birth US (reference) Mexico Elsewhere Unknown Education Level 4 < High School (reference) High School or GED > High School Unknown 3307 3347 1834 2143 2120 293 264 6213 287 153 1 1999 1492 3050 113 Int. J. Environ. Res. Public Health 2009, 6 1641 differed by gender and country of birth only for adults, with females and those born in Mexico having significantly lower SHS exposure. Blacks of all ages had greater prevalence rates of detectable cotinine compared to Whites, while children of any other race/ethnicity groups and Mexican American adolescents were less likely to have detectable cotinine than Whites. Non-Hispanic Blacks of all ages had significantly decreasing prevalence of detectable cotinine over the 8-year time period, and Mexican American children and adolescents had significantly decreasing trends in both the prevalence of cotinine and geometric mean of cotinine concentration over the same period. Table 2. Percentages of nonsmokers with self-reported secondhand smoke exposure1 by socio-demographic characteristics and age group, and odds ratios from multivariate logistic regression model1: U.S., 1999-2006. Sample Size 3 6654 Children (3-11) Adjusted Unadjusted Odds Ratio % (95% CI) 20.8 Sample Size 3 6170 Adolescents (12-19) Adjusted Unadjusted Odds Ratio % (95% CI) 18.7 Sample Size 3 9320 Adults (20+) 2 Adjusted Unadjusted Odds Ratio % (95% CI) 14.5 19.6 22.2 23.1 27.0 8.5 17.3 14.3 21.4 5.3 14.1 -- 32.4 26.7 14.7 28.8 1.24 (1.06- 1.46)* 0.64 (0.50- 0.81)* 0.14 (0.10- 0.21)* 0.40 (0.24- 0.65)* 0.46 (0.26- 0.81)* 0.37 (0.21- 0.66)* 0.55 (0.28- 1.06) -- 0.66 (0.50- 0.86)* 0.41 (0.29- 0.59)* 1.03 (0.47- 2.25) 2967 3203 1494 2033 2240 230 173 5245 658 266 1 2006 1332 2687 145 18.2 19.2 20.1 25.4 9.4 10.6 13.7 19.7 6.1 10.6 -- 26.4 26.0 13.6 29.1 1.04 (0.85- 1.26) 0.87 (0.67- 1.13) 0.24 (0.17- 0.36)* 0.36 (0.18- 0.73)* 0.53 (0.27- 1.02) 0.40 (0.25- 0.64)* 0.49 (0.29- 0.84)* -- 0.70 (0.48- 1.03) 0.34 (0.24- 0.47)* 1.10 (0.54- 2.24) 3939 5381 4775 1567 2282 283 413 7005 1336 976 3 2840 2043 4421 16 18.7 11.3 13.3 19.9 15.7 18.4 15.9 14.5 14.6 14.3 -- 17.4 18.7 11.9 -- 0.52 (0.45- 0.61)* 1.59 (1.30- 1.93)* 1.22 (0.95- 1.58) 1.36 (0.96- 1.91) 1.85 (1.25- 2.74)* 0.69 (0.52- 0.92)* 0.74 (0.56- 0.99)* -- 1.15 (0.90- 1.48) 0.70 (0.55- 0.89)* --