Table 4.

Associations between multiple-metal exposure and raw developmental scores on the Bayley Scales of Infant Development III.

Outcome	Cluster 2 “Low-to-moderate metal exposure” β  ± SE	Cluster 3 “High lead and cadmium” β  ± SE	Cluster 4 “High metal exposure” β  ± SE
Complete-case analysis1,2,3
Cognitive scale	−1.42 ± 1.95	−1.27 ± 2.76	1.64 ± 3.83
Expressive vocabulary scale	−1.13 ± 2.53	0.48 ± 3.58	3.96 ± 4.97
Receptive vocabulary scale	−0.32 ± 2.33	2.28 ± 3.30	6.70 ± 4.56
Imputed-data analysis1,2,3
Cognitive scale	0.35 ± 2.68	1.72 ± 3.35	5.10 ± 16.23
Expressive vocabulary scale	2.24 ± 4.89	4.54 ± 4.95	0.59 ± 24.08
Receptive vocabulary scale	1.34 ± 4.04	3.87 ± 3.91	12.07 ± 25.85

¹Sample size was 47–49 for complete-case analysis and 92 for models with imputed data; ²cluster 1 (“Low metal exposure”) served as the reference group; ³models adjusted for child age in months, maternal IQ and depressive scores, household density, HOME score, socioeconomic status, tester, and the child's hemoglobin value.