title: [New spirometric reference values for children and adolescents in Germany considering height and non-linear age effects: the LUNOKID-study].
abstract: BACKGROUND
  Comparing children's lung function with reference values is important for diagnosing respiratory diseases. The values by Zapletal et al., commonly used nowadays, are not appropriate for the current stage of children's development. We have now developed new reference values and a lower limit of normal (LLN) for children in Germany, divided into small-range age and height categories.
  
  
  METHODS
  We examined 4- to 18-year-old children in 3 German communities under field conditions. 1943 children were healthy and had a visually acceptable lung function which also fulfilled international quality criteria. We used the regression model LMS, which was introduced by Stanojevic and Quanjer in this context.
  
  
  RESULTS
  There were significant differences between the measured lung function and the predicted values according to Zapletal et al. The lung function did not only depend on the child's height, but also in a non-linear way on the age. The variation coefficient did not depend on age.
  
  
  CONCLUSIONS
  To avoid diagnostic errors, the currently often used reference values according to Zapletal et al. should no longer be used. The non-linear dependence on age corresponds to the recently published results by Stanojevic and Quanjer.
authors: Epidemiologie, IUF-Leibniz-Institut für umweltmedizinische Forschung, Düsseldorf.
authors: A
authors: A
authors: Hüls
authors: Epidemiologie, IUF-Leibniz-Institut für umweltmedizinische Forschung, Düsseldorf.
authors: U
authors: U
authors: Krämer
authors: Klinik für Kinder- und Jugendmedizin, Marienhospital, Wesel.
authors: M
authors: M
authors: Gappa
authors: Abteilung für Anästhesiologie und Intensivmedizin, Medizinische Hochschule, Hannover.
authors: C
authors: C
authors: Müller-Brandes
authors: Epidemiologie, IUF-Leibniz-Institut für umweltmedizinische Forschung, Düsseldorf.
authors: G
authors: G
authors: Seitner-Sorge
authors: Klinik für Kinder- und Jugendmedizin, Marienhospital, Wesel.
authors: A
authors: A
authors: von Berg
authors: Zentrum für Kinder- und Jugendmedizin, Heinrich-Heine Universität, Düsseldorf.
authors: A
authors: A
authors: Schuster
authors: Klinik für Kinder- und Jugendmedizin, Marienhospital, Wesel.
authors: C
authors: C
authors: Beckmann
authors: Universitätskinderklinik, LMU, München.
authors: S
authors: S
authors: Illi
authors: Zentrum für Kinder- und Jugendmedizin, Heinrich-Heine Universität, Düsseldorf.
authors: M
authors: M
authors: Wisbauer
authors: Klinik für Kinder- und Jugendmedizin, Marienhospital, Wesel.
authors: D
authors: D
authors: Berdel
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D000375:Aging / Q000502:physiology*; D001827:Body Height / Q000502:physiology*; D002648:Child; D003198:Computer Simulation; D003936:Diagnosis, Computer-Assisted / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008954:Models, Biological; D017711:Nonlinear Dynamics; D015272:Pulmonary Medicine / Q000592:standards*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D013147:Spirometry / Q000592:standards* / Q000706:statistics & numerical data*; D013990:Tidal Volume / Q000502:physiology*