Table 3.
Ancillary Analysis. Mean 16-Year Developmental Test Scores By Randomization Group Excluding Participants Who Received Iron Therapy at 12 or 18 Months
| Outcome | N | Mean (sd)a | Adjusted difference b | P-Value b | |
|---|---|---|---|---|---|
| Iron-Fortified | Low-Iron | (95%CI) | |||
| IQ, Matrix Reasoning | 355 | 7.5 (2.3) | 7.1 (2.3) | 0.33 (−0.2, 0.8) | 0.19 |
| IQ, Verbal Similarities | 355 | 7.9 (2.2) | 8.3 (2.1) | −0.5 (−0.9, −0.01) | 0.04 |
| Spatial, Rey Copy | 240 b | 32.8 (4.0) | 33.5 (2.5) | −0.8 (−1.7, 0.1) | 0.09 |
| Spatial, Rey Memory | 240 b | 22.2 (6.2) | 23.7 (5.6) | −1.7 (−3.2, −0.1) | 0.03 |
| Arithmetic Achievement, WRAT | 355 | 82.0 (10.4) | 84.7 (11.5) | −3.0 (−5.2, −0.8) | <0.01 |
| Reading Achievement, Vocabulary | 337 | 21.4 (7.4) | 22.0 (7.1) | −0.9 (−2.5, 0.6) | 0.15 |
| Reading Achievement, Comprehension | 342 | 10.9 (4.5) | 12.2 (4.6) | −1.4 (−2.3, −0.4) | <0.01 |
| Visual Motor Integration, VMI | 353 | 84.8 (11.8) | 86.8 (10.1) | −2.0 (−4.3, 0.3) | 0.08 |
| Motor coordination, VMI supplemental | 353 | 88.9 (9.8) | 89.8 (9.8) | −0.8 (−2.9, 1.2) | 0.42 |
CI = confidence interval
a
Unadjusted mean (sd)
b
Test of difference in means adjusting for birthweight, gestational age, sex, maternal IQ, HOME environment, SES, average ml/day of formula intake, and age of assessment
c
Administration of Rey tasks was stopped approximately halfway through follow-up to reduce testing burden on participant.