Figure 1

Adjusted* mean differences in child neurobehavioral outcomes at age 6.5 years by exposure to prenatal and postnatal parental smoking. (a) Full-scale IQ. (b) Total difficulties. (c) Externalizing behaviors. (d) Internalizing behaviors. * Partial adjustment model controlled for cluster, child sex and age at outcome measures; full model additionally adjusted for maternal and paternal age, height, education, and occupation, marital status of parents at birth, birth order, maternal drinking during pregnancy, and paternal smoking at 6.5 years age (for maternal smoking only).