Table 1

Characteristics of participants

Population descriptorNo head injury (n=90 371)Head injury (n=290)
Gender*
 n (%)
  Male46 348 (51.3)162 (55.9)
  Female44 019 (48.7)128 (44.1)
Townsend deprivation index quintile†
 n (%)
  1 (least deprived) (reference)17 395 (19.4)47 (16.4)
  216 863 (18.8)43 (15.0)
  317 301 (19.3)56 (19.5)
  417 909 (19.9)65 (22.6)
  5 (most deprived)20 339 (22.6)76 (26.5)
Apgar score‡
 Median (IQR)9 (5–9)9 (7–9)
Gestational age§
 Mean (SD) weeks39.3 (2.1)39.2 (2.1)
Birth weight¶
 Mean (SD) kg3.4 (0.6)3.3 (0.6)
Age at KS1 assessment
 Mean (SD) years7.3 (0.3)7.3 (0.3)
  • *Data missing for n=4, 0.05%.

  • †Data missing for n=567, 0.6%.

  • ‡Data missing for 40 006, 44.1%.

  • §Data missing for 15 518, 17.1%).

  • ¶Data missing for n=10 129, 11.2%.