Table 2. Intercorrelations among Model Variables and Correlations between Model Variables and Controls.
| Model variables | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|
| 1. Iron deficient (ID) onlya | – | – | .00 | .02 | -.01 | -.06 | -.09* | -.01 |
| 2. Iron-deficient anemic (IDA)b | – | – | .10** | .10** | -.01 | .09* | .06 | .09* |
| 3. Poor emotion regulation - 10 yrs | .04 | .14*** | – | .49*** | .31*** | .28*** | .09* | .05 |
| 4. Sluggish cognitive tempo sym - 10 yrs | .06 | .11** | .49*** | – | .19*** | .30*** | .12** | .08 |
| 5. Rule-breaking - adolescence | -.01 | -.01 | .35*** | .21*** | – | .49*** | .48*** | .22*** |
| 6. Risk-taking - adolescence | -.05 | .02 | .30*** | .30*** | .49*** | – | .49*** | .31*** |
| 7. Excessive-problematic alcohol use – adolescence | -.08* | -.02 | .10* | .12** | .50*** | .51*** | – | .38*** |
| 8. Risky sexual behavior - adolescence | .01 | .03 | .06 | .09* | .27*** | .37*** | .48*** | – |
| Controls | ||||||||
| Child sex (1=male) | .05 | .17*** | .11** | .04 | .13** | .13** | .08* | .02 |
| Family socioeconomic - infancy | -.04 | -.11** | .01 | .01 | .04 | .06 | .03 | .01 |
| Family stressors – 1 yr | .02 | .04 | .11** | .08* | .08 | .03 | .07 | .04 |
| HOME environment – 1yr | -.04 | -.03 | -.05 | -.06 | -.08* | -.05 | -.07 | -.05 |
| Mothers' education - 1 yr | -.02 | -.09* | -.13** | -.05 | -.04 | -.03 | -.02 | .02 |
| Iron supplementationc | -.15*** | -.40*** | -.00 | .06 | .07 | .13** | .22*** | .20*** |
| Child age – 10 yrs | -.02 | -.02 | .08* | -.01 | -.01 | .04 | .00 | .04 |
| Age at adolescent follow-up | -.02 | -.13** | -.01 | -.01 | .07 | .23*** | .40*** | .40*** |
Note. The intercorrelations above the diagonal for variables 1-8 control for the relevant control variables; the coefficients below the diagonal include no controls. Variables 3 – 8 are latent variables. Father present in the household at 1 year, whether breastfeeding was the sole source of milk at 6 months, and girls' age at menarche did not correlate significantly with any of the model variables and are not shown.
0 = iron sufficient, 1 = iron deficient without anemia at 6, 12 or 18 months; excludes those diagnosed as ID-anemic. Ns ranged from 885-931.
0 = iron sufficient, 1 = iron-deficient with anemia at 6, 12, or 18 months; excludes those who were iron deficient only. Ns ranged from 763-806.
0 = no iron supplementation in infancy, 1 = some form of iron supplementation as part of the preventive trial.
p < .05.
p < .01.
p < .001.