Boxplot of the white matter abnormality scores for the four ELBW infant groups show that the more previous brain hemorrhage, the more white matter abnormality at term-equivalent age. A score of 6 means normal white matter. Any score greater than 6 means abnormality. The line in the middle for each box is the median score for each group, and the box contains scores in 25-75 percentiles. Minimum/Maximum scores in each group are also marked. A one way ANOVA revealed significant effect (p<0.001) of brain hemorrhage on white matter abnormality score at term-equivalent age in ELBW infants.
ELBW_NO: ELBW infants without old blood product deposition on MRI at term-equivalent age;
ELBW_BD: ELBW infants with old blood product on MRI but no IVH diagnosis by ultrasound;
ELBW_12: ELBW infants with grades 1 or 2 IVH diagnosis;
ELBW_34: ELBW infants with grades 3 or 4 IVH diagnosis.