Low-level environmental lead exposure in childhood and adult intellectual function: a follow-up study

Table 2 Unadjusted Changes in IQ for Each Increase in the Blood Lead Concentration of 1 microgram per Deciliter

Type of Blood Lead		Full-Scale IQ			Verbal IQ			Performance IQ
Measurement	n	β ± SE	p	R²	β ± SE	p	R²	β ± SE	p	R²
Average late childhood	42	-1.89 ± 0.70	0.01	0.154	-1.98 ± 0.76	0.12	0.145	-1.33 ± 0.66	0.05	0.091
(mean of 4 yr and 10 yr)		(-3.30, -0.47)			(-2.68, 0.01)			(-2.68, 0.01)
Average	43	-1.66 ± 0.75	0.03	0.106	-1.22 ± 0.83	0.15	0.050	-1.68 ± 0.68	0.02	0.129
(mean of all available)		(-3.18, -0.14)			(-3.06, -0.30)			(-3.06, -0.30)
6 months	39	-0.90 ± 0.41	0.03	0.117	-0.80 ± 0.45	0.08	0.080	-0.81 ± 0.37	0.03	0.115
		(-1.73, -0.77)			(-1.71, 0.11)			(-1.57, -0.06)
4 years	40	-1.26 ± 0.58	0.04	0.110	-0.96 ± 0.64	0.14	0.055	-1.25 ± 0.51	0.02	0.136
		(-2.43, -0.09)			(-2.27, 0.35)			(-2.29, 0.22)
10 years	37	-1.95 ± 0.80	0.02	0.145	-2.84 ± 0.81	0.001	0.258	-0.52 ± 0.72	0.48	0.520
		(-3.56, -0.33)			(-4.49, 1.19)			(-1.98, 0.99)

ISSN: 1476-069X