Table 1

Infant characteristics and social factors at randomisation

Infant characteristicsIntervention (N=72)Control (N=74)
BW, mean (SD), g1396 (429)1381 (436)
 400–1000 g, n (%)20 (28)20 (27)
 1001–1500 g, n (%)15 (21)20 (27)
 1501–2000 g, n (%)37 (51)34 (46)
GA, mean, (SD), weeks30.2 (3.1)29.9 (3.5)
 <28 weeks, n (%)17 (24)19 (27)
 28–32 weeks, n (%)36 (50)37 (50)
 ≥33 weeks, n (%)19 (26)18 (24)
SGA* (%)11 (13)10 (14)
Twins, n (%)16 (22)14 (19)
Prenatal steroids, n (%)53 (74)57 (77)
SNAP-II score, mean (SD)8.3 (10.9)10.4 (11.3)
CRIB score, mean (SD) (N=85)3.2 (2.8)2.7 (2.9)
Received ventilation, n (%)29 (40)37 (50)
Duration of ventilation, mean (SD), d (N=66)7.0 (18.6)7.1 (17.3)
Postnatal steroid use, n (%)9 (13)10 (14)
Oxygen therapy at 36 weeks of gestation, n (%)11 (15)14 (19)
Abnormal cerebral ultrasound, n (%)
 IVH grade 1 or 27 (10)8 (11)
 IVH grade 3 or 43 (4)5 (7)
 Periventricular leukomalacia4 (6)8 (11)
Maternal and social characteristics
 Mother's age, mean (SD), years30.8 (6.1)29.1 (6.4)
 Firstborn children, n (%)40 (56)37 (54)
 Mother's education, mean (SD), years (N=131)†14.6 (2.8)13.5 (3.2)
 Father’s education mean, (SD), years (N=131)†13.8 (3.1)13.5 (3.2)
 Mother's monthly income‡15.8 (7.7)14.6 (6.7)
 Father’s monthly income‡21.1 (8.7)19.9 (8.1)
  • SNAP-II indicates the Score for Neonatal Acute Physiology II (includes mean blood pressure, lowest temperature, P02/fraction of inspired oxygen ratio, serum pH, multiple seizures and urine output); CRIB, Clinical Risk Index for Babies (includes BW, GA, congenital malformations, maximal base deficits in the first 12 h, minimal appropriate fraction of inspired oxygen in the first 12 h and maximal appropriate fractions of inspired oxygen in the first 12 h).

  • *SGA, defined as a BW >2 SD below the mean for GA.

  • †Calculated for 131 families due to 15 twin pairs.

  • ‡Average monthly income (SD) in 1000 Norwegian kroner.

  • BW, birth weight; GA, gestational age; IVH, intraventricular haemorrhage; SGA, small for gestational age.