Table 3.

Adjusted mean cognitive test scores (mean ± SE) at increasing log cotinine levels for children 6–16 years of age, controlling for potential covariates, NHANES III (1988–1994).

Cotinine level (ng/mL)	Math	Reading	Block design	Digit span
< 0.1	95.83 ± 0.94	94.67 ± 0.81	9.91 ± 0.15	8.87 ± 0.13
0.1–1	94.69 ± 0.79	92.12 ± 0.82	9.59 ± 0.10	8.67 ± 0.09
1–3	94.72 ± 1.05	91.88 ± 1.34	9.43 ± 0.21	8.87 ± 0.22
3–15	88.69 ± 1.93	87.13 ± 1.93	8.52 ± 0.30	8.00 ± 0.29