Table 1. Clinical Factors and 4.5 Year Outcomes by Level of Maternal of Education.
| Clinical Factor | Maternal Level of Education, No./Total No. (%) | P Value | ||
|---|---|---|---|---|
| Primary or Secondary School (n = 29) | Undergraduate Degree (n = 134) | Postgraduate Degree (n = 34) | ||
| Prenatal | ||||
| Maternal age, median (IQR), y | 30.5 (27-36.8) | 32.1 (28.3-36.9) | 32.4 (30.6-36.6) | .28 |
| Preeclampsia | 7/29 (24.1) | 36/134 (26.9) | 6/34 (17.7) | .51 |
| Gestational diabetes | 4/29 (13.8) | 11/134 (8.2) | 0 | .40 |
| Prenatal steroids | 25/29 (86.2) | 123/134 (91.8) | 29/34 (85.3) | .30 |
| Prenatal magnesium sulfate | 8/29 (27.6) | 27/134 (20.2) | 6/34 (17.7) | .66 |
| Histological chorioamnionitis | 12/27 (44.4) | 47/132 (35.6) | 12/33 (36.4) | .69 |
| Small for gestational age | 7/29 (24.1) | 24/134 (17.9) | 3/34 (8.8) | .25 |
| Birth and neonatal intensive care unit course | ||||
| Male | 17/29 (58.6) | 71/134 (53.0) | 18/34 (52.9) | .78 |
| Gestational age, mean (SD), wk | 28.0 (2.1) | 27.9 (2.2) | 28.4 (2.6) | .53 |
| Birth weight, mean (SD), g | 1046.7 (303.6) | 1038.3 (318.7) | 1132.4 (347.9) | .31 |
| Total ventilation, median (IQR), d | 5.5 (1.5-37.0) | 7.0 (1.0-35.0) | 2.0 (1.0-29.0) | .60 |
| Chronic lung disease, defined as oxygen at 36 weeks’ postmenstrual age | 5 (16.7) | 25 (18.7) | 7 (20.6) | .69 |
| Retinopathy of prematurity | 12/24 (50.0) | 51/109 (46.8) | 7/27 (25.9) | .11 |
| Postnatal infection | 14/29 (48.3) | 76/133 (57.1) | 14/34 (41.2) | .23 |
| Postnatal dexamethasone | 7/29 (24.1) | 24/134 (17.9) | 8/33 (24.2) | .60 |
| Punctate white matter injury present | 11/29 (37.9) | 37/134 (27.6) | 8/34 (23.5) | .49 |
| Punctate white matter injury volume, median (IQR), mm3 | 39.4 (20.3-95.5) | 64.0 (19.5-431.9) | 28.2 (15.2-253.9) | .56 |
| Severe intraventricular hemorrhage (grade 3 or periventricular hemorrhagic infarction >2 cm) | 1/26 (3.9) | 3/128 (2.4) | 2/33 (6.1) | .59 |
| Outcome at 4.5 y | ||||
| Full-scale IQ, mean (SD) | 99.6 (13.6) | 101.0 (15.7) | 108.3 (9.5) | .02 |
| Wechsler Primary and Preschool Scale of Intelligence verbal IQ, mean (SD) | 99.0 (15.5) | 100.5 (16.1) | 108.4 (12.2) | .02 |
| Wechsler Primary and Preschool Scale of Intelligence performance IQ, mean (SD) | 103.8 (11.2) | 103.7 (13.8) | 107.5 (8.1) | .01 |
| Wechsler Primary and Preschool Scale of Intelligence processing speed, mean (SD) | 94.4 (9.9) | 96.8 (14.5) | 100.7 (10.4) | .09 |
| Movement Assessment Battery for Children percentile score, median (IQR) | 25 (5-50) | 25 (2-63) | 56 (16-91) | .04 |
Abbreviation: IQR, interquartile range.