Table 1

Comparison of the demographics of all BiB participants with linked EYFSP and gestational age data compared with data available from the whole cohort

EYFSP and gestational age
n=10 390
Whole BiB cohort
n=13 818
Educational factors10 570*
 EYFSP, n (%) ‘meeting GLD’†6161 (59)6253 (59)
 English as an additional language, n (%)4720 (45)4788 (45)
  Missing111 (1)114 (1)
Perinatal factors13 525*
 Gestational age (weeks), n (%)‡
  <32 81 (<1)149 (1)
  32–33 65 (<1)110 (<1)
  34–36 478 (5)646 (5)
  37–38 2355 (23)3028 (22)
  39–41 7269 (70)9047 (67)
  >42 (late term)142 (1)185 (1)
 Month of birth, n (%) ‘Summer Born’§3750 (36)3816 (36)
 Small for gestational age, n (%)1449 (14)1857 (14)
 Large for gestational age, n (%)711 (7)954 (7)
 Sex ratio (male:female)49:5152:48
 Parity, median (range)1 (0–10)1 (0–10)
Socioeconomic factors11 396*
 Mother receiving means-tested benefits, n (%)3683 (35)4639 (41)
  Missing1859 (18)39 (<1)
 Maternal educational level (equivalised), n (%)
  Higher than A level1991 (19)2912 (26)
  A level or equivalent1277 (12)1644 (14)
  5 GCSEs or equivalent2717 (26)3488 (31)
  <5 GCSEs or equivalent1922 (18)2453 (22)
  Foreign unknown or other523 (5)741 (7)
  Unable to answer100 (<1)128 (1)
  Missing1860 (18)30 (<1)
  • *n within the whole cohort who consented and had linked records for this aspect of data collection.

  • †As defined by Cotzias and Whitehorn.9

  • ‡Categories suggested by Jaekel et al.11

  • §Born between 1 April and 31 August.

  • BiB, Born in Bradford; EYFSP, Early Years Foundation Stage Profile; GCSE, General Certificate of Secondary Education; GLD, Good Level of Development.