title: Spirometry centile charts for young Caucasian children: the Asthma UK Collaborative Initiative.
abstract: BACKGROUND
  Advances in spirometry measurement techniques have made it possible to obtain measurements in children as young as 3 years of age; however, in practice, application remains limited by the lack of appropriate reference data for young children, which are often based on limited population-specific samples.
  
  
  OBJECTIVE
  We aimed to build on previous models by collating existing reference data in young children (aged 3-7 yr), to produce updated prediction equations that span the preschool years and that are also linked to established reference equations for older children and adults.
  
  
  METHODS
  The Asthma UK Collaborative Initiative was established to collate lung function data from healthy young children aged 3 to 7 years. Collaborators included researchers with access to pulmonary function test data in healthy preschool children. Spirometry centiles were created using the LMS (lambda, micro, sigma) method and extend previously published equations down to 3 years of age.
  
  
  RESULTS
  The Asthma UK centile charts for spirometry are based on the largest sample of healthy young Caucasian children aged 3-7 years (n = 3,777) from 15 centers across 11 countries and provide a continuous reference with a smooth transition into adolescence and adulthood. These equations improve existing pediatric equations by considering the between-subject variability to define a more appropriate age-dependent lower limit of normal. The collated data set reflects a variety of equipment, measurement protocols, and population characteristics and may be generalizable across different populations.
  
  
  CONCLUSIONS
  We present prediction equations for spirometry for preschool children and provide a foundation that will facilitate continued updating.
authors: Portex Unit, Respiratory Physiology and Medicine, UCL, Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK. s.stanojevic@ich.ucl.ac.uk
authors: Sanja
authors: S
authors: Stanojevic
authors: Angie
authors: A
authors: Wade
authors: Tim J
authors: TJ
authors: Cole
authors: Sooky
authors: S
authors: Lum
authors: Adnan
authors: A
authors: Custovic
authors: Mike
authors: M
authors: Silverman
authors: Graham L
authors: GL
authors: Hall
authors: Liam
authors: L
authors: Welsh
authors: Jane
authors: J
authors: Kirkby
authors: Wenche
authors: W
authors: Nystad
authors: Monique
authors: M
authors: Badier
authors: Stephanie
authors: S
authors: Davis
authors: Steven
authors: S
authors: Turner
authors: Pavilio
authors: P
authors: Piccioni
authors: Daphna
authors: D
authors: Vilozni
authors: Howard
authors: H
authors: Eigen
authors: Helen
authors: H
authors: Vlachos-Mayer
authors: Jinping
authors: J
authors: Zheng
authors: Waldemar
authors: W
authors: Tomalak
authors: Marcus
authors: M
authors: Jones
authors: John L
authors: JL
authors: Hankinson
authors: Janet
authors: J
authors: Stocks
mesh_terms: D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005541:Forced Expiratory Volume; D006801:Humans; D012016:Reference Values; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013147:Spirometry / Q000592:standards*; D006113:United Kingdom; D044465:White People