Figure 1.

Path diagrams of structural equation models to test the effect of prenatal tobacco exposure on the specific mental health outcome at ages 7–11, shown in the upper panel and to test a mediating role of stress reactivity at ages 2–6 in the effect of prenatal tobacco exposure on the specific mental health outcome at ages 7–11 (that is, a mediating effect), after controlling for the same mental health outcome at age 4, shown in the lower panel. A separate model was estimated for each of the five mental health outcomes. Potential confounding effects of maternal, paternal, teacher, and child variables on the stress reactivity and the mental health outcome were controlled for (paths are not shown for simplicity).