Research Article

Do US Ambient Air Lead Levels Have a Significant Impact on Childhood Blood Lead Levels: Results of a National Study

Table 4

Multivariate negative binomial regression using robust variance estimation predicting number of children with BLL ≥ 10 μg/dL per US county.

Negative binomial regression
VariablesRelative riskRobust SEP value95% CI

NATA*1.360.1760.017(1.06, 1.75)
% pre50 housing1.050.0020.000(1.04, 1.05)
Urban-rural
 Urban(reference)
 Suburban0.860.1350.337(0.63, 1.17)
 Rural0.660.1100.013(0.48, 0.92)
% Black1.010.0020.000(1.00, 1.01)
Targeted/mandatory testing0.640.0410.000(0.56, 0.72)

Note: the predictor of NATA05 air lead was scaled to 100* (the original NATA05 air lead).