TABLE 1—
Results of Univariate Analysis of Cotinine Levels by Child Characteristics, Black and White Children With Lead Levels of ≤ 9 μg/dL: United States, 2011–2012
| Characteristic | No. of Children | Cotinine Level, ng/g, Median (Range) | P |
| Racea | < .001b | ||
| Black | 723 | 0.66 (< 0.3–35) | |
| White | 815 | 0.30 (< 0.3–41) | |
| Age, moc | < .001d | ||
| ≤12 | 205 | < 0.3 (< 0.3–24) | |
| 13–24 | 665 | 0.49 (< 0.3–41) | |
| 25–36 | 471 | 0.48 (< 0.3–28) | |
| >36 | 179 | 0.76 (< 0.3–34) | |
| Gendere | .728b | ||
| Female | 747 | 0.46 (< 0.3–35) | |
| Male | 768 | 0.51 (< 0.3–41) | |
| Collection month | .004b | ||
| June or July | 525 | 0.59 (< 0.3–41) | |
| November, December, January, or February | 1010 | 0.40 (< 0.3–34) | |
| State smoking rate, %f | < .001 | ||
| ≤ 17.5 | 319 | < 0.3 (< 0.3–25) | |
| 17.6–20.0 | 507 | 0.30 (< 0.3–41) | |
| 20.1–22.5 | 483 | 0.72 (< 0.3–27) | |
| > 22.5 | 193 | 1.05 (< 0.3–34) | |
| Medicaid recipient | < .001b | ||
| No | 954 | < 0.3 (< 0.3–41) | |
| Yes | 585 | 0.94 (< 0.3–34) | |
| Average winter temperature, °F g | < .001 | ||
| < 32 | 562 | < 0.3 (< 0.3–25) | |
| ≥ 32 | 940 | 0.63 (< 0.3–41) | |
| Average summer temperature, °Fh | < .001 | ||
| < 74.9 | 746 | 0.30 (< 0.3–34) | |
| ≥ 75 | 756 | 0.67 (< 0.3–41) | |
| Lead level, μg/dLi | < .001d | ||
| < 1 | 306 | < 0.3 (< 0.3–34) | |
| 1 | 611 | 0.37 (< 0.3–35) | |
| 2 | 314 | 0.76 (< 0.3–26) | |
| 3 | 161 | 0.92 (< 0.3–28) | |
| 4 | 70 | 1.07 (< 0.3–22) | |
| 5 | 34 | 1.36 (< 0.3–24) | |
| 6 | 16 | 0.40 (< 0.3–41) | |
| 7 | 13 | 0.97 (< 0.3–3) | |
| 8 | 7 | 5.06 (< 0.3–11) | |
| 9 | 7 | 0.97 (< 0.3–4) | |
| Total | 1541 | 0.48 (< 0.3–41) |
One child was of mixed race and was not included in the race breakdown, and data on race were missing for 2 children.
Based on nonparametric Wilcoxon rank sum test.
Data on age were missing for 21 children. Age ranged from 0.4–47.9 months.
Derived from nonparametric Spearman correlation.
Data on gender were missing for 26 children.
The state smoking rate range is 9.8%–25.6%. The nonparametric correlation between cotinine and the state smoking prevalence is 0.23. Data on collection month were missing for 6 children.
The average winter temperature range is 12.1–59.4 °F. The nonparametric correlation between cotinine and state winter temperature is 0.14. Data on average winter temperature were missing for 39 children.
The average summer temperature range is 63.7–81.1 °F. The nonparametric correlation between cotinine and state summer temperature is 0.12. Data on average summer temperature were missing for 39 children.
Data on lead level were missing for 2 children.