title: Early termination of exhalation: effect on spirometric parameters in healthy preschool children.
abstract: OBJECTIVE
  To evaluate the acceptability and reproducibility of spirometry in preschool children; to estimate the effect size of early termination of exhalation (ETE) on FVC, FEV(1) and FEV(0.5); and to evaluate the validity of FEV(0.5) in curves with ETE.
  
  
  METHODS
  Spirometric data were obtained from 240 healthy preschool children, who were selected by simple sampling. On the basis of the best curve from each child according to the end of exhalation, three groups were formed: no ETE (nETE); ETE and flow ≤ 10% of the highest PEF (ETE≤10); and ETE and flow > 10% of the highest PEF value (ETE>10). The reproducibility of FVC, FEV(1) and FEV(0.5) was compared among the three groups. The effect of ETE on FVC, FEV(1), and FEV(0.5) was assessed.
  
  
  RESULTS
  Of the 240 children tested, 112 (46.5%)-82 (34.0%) of those in the nETE group and 30 (12.5%) of those in the ETE≤10 group--had acceptable curves for all the parameters. In 64 (27.0%) of those in the ETE>10 group, the curves were acceptable only for FEV(0.5), increasing the proportion of children with valid FEV(0.5) to 73.0%. There were no significant differences between the nETE and ETE≤10 groups in terms of the mean values of the parameters assessed.
  
  
  CONCLUSIONS
  Maneuvers with ETE and flow ≤ 10% of the highest PEF are valid. In individuals with a flow > 10% of the highest PEF value, these maneuvers are only valid for FEV(0.5).
authors: Graduate Program in Child and Adolescent Health, Federal University of Pernambuco – Recife, Brazil. edjaneburity@hotmail.com
authors: Edjane Figueiredo
authors: EF
authors: Burity
authors: Carlos Alberto de Castro
authors: CA
authors: Pereira
authors: José Ângelo
authors: JÂ
authors: Rizzo
authors: Emanuel Sávio Cavalcanti
authors: ES
authors: Sarinho
authors: Marcus Herbert
authors: MH
authors: Jones
mesh_terms: D001249:Asthma / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D045853:Exhalation / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D012120:Respiration Disorders / Q000175:diagnosis*; D012129:Respiratory Function Tests / Q000379:methods / Q000592:standards*; D013147:Spirometry / Q000523:psychology