TABLE 5

Multivariate Linear Regression Models Testing Main and Interactive Effects of Prenatal Chlorpyrifos Exposure on 12-, 24-, and 36-Month PDI Scores, Adjusted for Race, Gender, Maternal Education, Maternal IQ, Gestational Age, and Prenatal ETS Exposure

VariableModel 1: 12 mo (n = 228)Model 2: 24 mo (n = 227)Model 3: 36 mo (n = 228)
B, Mean ± SEPB, Mean ± SEPB, Mean ± SEP
Constant112.28 ± 34.64.0081.05 ± 32.45.0164.56 ± 36.64.079
Prenatal chemical exposures
    ETSa0.31 ± 1.76.862.83 ± 1.63.08−0.14 ± 1.79.940
    Chlorpyrifosb−3.30 ± 2.11.121.17 ± 1.98.56−6.46 ± 2.18.003
Covariates
    Race/ethnicityc−2.00 ± 1.81.272.15 ± 1.70.213.88 ± 1.82.034
    Genderd0.11 ± 1.64.950.08 ± 1.54.96−2.95 ± 1.66.077
    Gestational age−0.16 ± 0.56.770.20 ± 0.53.701.38 ± 0.64.033
    Maternal IQe−0.71 ± 6.26.910.09 ± 5.56.99−5.78 ± 6.08.343
    Low maternal educationf−0.81 ± 1.77.65−1.26 ± 1.66.451.69 ± 1.81.350
    HOME score−0.08 ± 0.15.610.09 ± 0.14.530.30 ± 0.16.057
R20.0240.0350.107
  • The sample included all children who had reached 3 years of age with data from the prenatal maternal interview, biomarkers of exposure, and complete data on all covariates. Sample sizes for age-specific models varied from 227 to 228 because of missed and/or unscorable assessments (<50). B indicates unstandardized regression coefficient.

  • a Prenatally exposed = 1; not exposed = 0.

  • b High exposure (>6.17 pg/g) = 1; low exposure (≤6.17 pg/g) = 0.

  • c Black = 2; Dominican = 1.

  • d Male = 2; female = 1.

  • e Measured with the Test of Nonverbal Intelligence, Second Edition,42 natural logarithmically transformed.

  • f No high school degree = 1; high school degree = 0.