Figure 4. Sex-specific associations between PM_2.5 exposure over gestation and attention domains and IQ: Comparing models based on levels averaged over pregnancy vs. identified sensitive windows.

This figure demonstrates estimated sex-specific associations and 95% CIs between prenatal PM_2.5 levels and each attention related domain (CPT-II) and full-scale IQ (WISC-IV) percentiles, obtained from multivariate regression models in which the prenatal PM_2.5 levels were (A) averaged across the sensitive windows identified by DLMs as in Figures 1 and 2, and (B) averaged over gestation. Higher CPT-II measures (in percentiles) indicate more omission errors, slower HRT, and more variability in response time throughout the test (HRT-SE), whereas lower full-scale IQ (standardized IQ score) indicates poorer composite intellectual performance. Models were adjusted for maternal age, race, education, prenatal/postnatal maternal smoking, parity, and blood lead level at neurodevelopmental testing.