. Author manuscript; available in PMC: 2013 Mar 1.

Published in final edited form as: Arch Pediatr Adolesc Med. 2011 Nov 7;166(3):208–215. doi: 10.1001/archpediatrics.2011.197

Table 2.

Ten-year outcomes for children who received iron-fortified vs. low-iron formula in infancy ^*

	Iron-fortified	Low-iron	Effect size (CI) ^†	p-value

N	244	229
IQ (WISC)	91.5 ± 0.9	93.3 ± 0.9	−0.13 (−0.25,− 0.01)	0.057
Spatial memory (KABC subtest)	86.8 ± 1.0	91.4 ± 1.0	−0.21 (−0.38, −0.04)	0.022
Arithmetic achievement (WRAT-R) ^‡	87.0 ± 0.8	88.4 ± 0.8	−0.10 (−0.19,− 0.01)	0.066
Visual-motor integration (VMI)	97.2 ± 0.9	99.8 ± 1.0	−0.21 (−0.40, −0.02)	0.046
Visual perception (VMI supplementary test)	90.8 ± 1.0	93.0 ± 1.1	−0.16 (−0.33, 0.01)	0.056
Motor coordination (VMI supplementary test)	88.7 ± 0.8	90.4 ± 0.8	−0.13 (−0.32, 0.05)	0.101
Motor proficiency (Bruininks-Oseretsky short form)	44.2 ± 0.6	45.1 ± 0.7	−0.08 (−0.25, 0.09)	0.265

Values are standard scores (mean ± SE), controlling for gender and gestational age. The norm is 100 ± 15 (SD) for all tests except for motor proficiency where the norm is 50 ± 10 SD.

^†

Effect size (CI, 95% confidence interval) calculated as score for iron-fortified group minus score for low-iron group divided by overall standard deviation.

^‡

We initially assessed reading using the WRAT, but due to the phonetic nature of Spanish, scores were extremely high with little variability, and the measure was dropped.