Table 1

Characteristics of the 89 surviving EP/ELBW-born children and the 57 term-born children in the regional cohort of Western Norway health region in 1999–2000

CharacteristicsEP/ELBW bornP value*Term bornP value†
AssessedNot assessed
Participants, n573257
Female gender, n (%)28 (49)12 (38)0.2926 (46)
Birth weight (g), mean (SD)842 (175)837 (142)0.743700 (434)
Gestational age (weeks), median (range)27 (24–31)27 (23-30)0.68
Small for gestational age, 0.10 percentile, n (%)20 (35)6 (19)0.11
Ventilator treatment, n (%)51 (89)21 (66)0.01
Days on ventilator, median (range)5 (0–24)2.5 (0–29)0.01
Bronchopulmonary dysplasia, n (%)31 (54)12 (38)0.13
Periventricular leucomalacia, n (%)4 (7)3 (9)0.70
Necrotising enterocolitis, n (%)1 (2)1 (3)0.59
Gastrostomy tube, n (%)0 (0)1 (3)0.36
Cerebral palsy at 5 years, n (%)3 (5)5 (16)0.13
Eating difficulties any time, n (%)16 (28)7 (22)0.52
Growth hormone treatment, n (%)2 (4)0 (0)0.53
Assessment at 11 years of age
Reduced mobility, n (%)2 (4)0 (0)0.16
Single parenthood, n (%)13 (23)6 (10)0.052
Mother higher education‡, n (%)31 (54)35 (61)0.85
Hearing impairment, n (%)6 (11)2 (4)0.16
Visual impairment, n (%)11 (19)5 (9)0.06
Inhaled corticosteroids, n (%)3 (5)3 (5)0.66
  • The enrolled subjects were examined in 2010–2011.

  • *P value for differences between the participating extremely preterm/extremely low birth weight (EP/ELBW)-born children and the EP/ELBW-born children not participating. Independent sample t-test, Mann-Whitney test and χ2 exact test as appropriate.

  • †P value for differences between the participation EP/ELBW-born and the TB control group. Wilcoxon signed-ranks test.

  • ‡High education defined by minimum 3 years of college or university degree.

  • EP/ELBW, Extremely preterm/extremely low birth weight; TB, term born.