Table VIII.
Conditional growth analyses of IQ at 30 years according to birthweight for gestational age z-score*
| Adjusted regression coefficient (95% CI) | P-value for interaction | |||
|---|---|---|---|---|
| Birthweight for gestational age z-score | ||||
| First tertile | Second tertile | Third tertile | ||
| Conditional length 2 years | 1.51(0.74to2.28) | 1.02(0.24to1.80) | 2.35(1.54to3.15) | .44 |
| Conditional relative weight 2 years | 0.26(−0.45to0.98) | 0.33(−0.42to1.07) | 0.88(0.15to1.62) | .20 |
| Conditional height 4 years | 0.98(0.25to1.71) | 0.31(−0.45to1.07) | −0.24(−0.97to0.50) | .04 |
| Conditional relative weight 4 years | −0.34(−1.08to0.39) | 0.00(−0.72to0.73) | −0.86(−1.58to−0.14) | .30 |
Adjusted for family income at birth, parental years of schooling, household index score, maternal skin color, maternal smoking during pregnancy, and breastfeeding duration.
*
Results are expressed as change in IQ(points) associated with one z-score of the conditional variable.