title: Revised birth centiles for weight, length and head circumference in the UK-WHO growth charts.
abstract: BACKGROUND
  The adoption in May 2009 by the UK of the WHO 2006 standard necessitated the provision of UK-based birth centiles for pre-term infants. The pre-existing British 1990 reference birth centiles, used in the UK since 1995, had been biased by the inclusion of post-natal data.
  
  
  OBJECTIVE
  To describe the construction of new UK birth centiles for weight, length and head circumference, based on British 1990 reference data, but excluding post-natal data.
  
  
  METHODS
  Birth data from the five original studies, collected between 1983-1993, were pooled and analysed by the LMS method, for the sexes separately. In addition, sex-specific composite centiles were constructed for infants born at term (37-42 completed weeks).
  
  
  RESULTS
  The birth data included 9443 weights, 985 lengths and 1841 head circumferences, covering 23-44 weeks gestation. The analysis provided LMS tables defining reference centiles for weight and head circumference from 23-42 weeks and for length from 26-42 weeks. The term centiles are for use at age 0 on the post-natal 0-1 year chart.
  
  
  CONCLUSIONS
  These new centiles, replacing those of the British 1990 reference, are more accurate than their predecessors which were biased due to the inclusion of post-natal data.
authors.affiliation: Medical Statistics, UCL Institute of Child Health, University College London, London, UK. tim.cole@ich.ucl.ac.uk
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Cole
authors.forename: Anthony F
authors.initials: AF
authors.lastname: Williams
authors.forename: Charlotte M
authors.initials: CM
authors.lastname: Wright
mesh_terms: D001724:Birth Weight; D001827:Body Height; D002508:Cephalometry; D005260:Female; D047109:Fetal Development; D005333:Fetus; D005865:Gestational Age; D057238:Growth Charts; D006257:Head / Q000033:anatomy & histology*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D010808:Physical Examination; D011247:Pregnancy; D012015:Reference Standards; D012016:Reference Values; D006113:United Kingdom; D014944:World Health Organization