Table 1

Description of 1997 cohort

Parameter22–27 weeksControl
Total live births223195
Survival to age 8 67.7 (151) 100 (195)
Proportion of survivors seen at age 8 95.4 (144) 88.7 (173)
Male gender seen at age 8 55.6 (80) 53.2 (92)
Mean (SD) gestation, completed weeks 25.6 (1.2) 39.3 (1.1)
Mean (SD) birth weight, g821 (175)3507 (453)
  • Numbers are % (N) unless otherwise stated.