title: Spirometric standards and patient characteristics: an exploratory study of factors affecting fulfillment in routine clinical practice.
abstract: BACKGROUND
  Spirometry is an apparently simple test, yet the recommended criteria for acceptability and reproducibility can be difficult to fulfill. This study aimed (1) to prospectively assess the number of tests that meet the American Thoracic Society/European Respiratory Society (ATS/ERS) 2005 acceptability and repeatability criteria in the routine practice of an experienced technician at a referral hospital's lung function laboratory, (2) to identify the most common errors, and (3) to explore patient characteristics possibly associated with failure to meet standards.
  
  
  METHODS
  We prospectively evaluated 257 consecutive spirometries supervised by the same technician, who gave priority to achieving a minimum of 3 correct maneuvers within a maximum of 8 attempts. We recorded FVC, FEV1, expiratory time (TE), back-extrapolated volume (VE), end-of-test volume (VEOT), number of maneuvers with and without errors, and errors (VE > 0.15 L or 5% of FVC, TE < 6 s, and VEOT ≥ 0.025 L for ≥ 1 s).
  
  
  RESULTS
  Two-hundred and fifteen spirometries (83.7%, 95% CI 78.6-87.7%) met the ATS/ERS 2005 criteria. Acceptability criteria were met in 73.9% (95% CI 71.2-76.3%) of the maneuvers and repeatability criteria in 90.7% (95% CI 86.5-93.6%). A mean ± SD of 3.3 ± 1.4 per subject was acceptable, and a mean ± SD of 4.5 ± 1.9 was obtained. TE and VEOT errors were the most common.
  
  
  CONCLUSIONS
  Nearly 15% of the subjects failed to fulfill all the ATS/ERS 2005 criteria for spirometry performed even though they were coached by a qualified and regularly trained technician in a hospital lung function laboratory. The fact that the ATS/ERS 2005 criteria cannot be met by all patients in optimal technical conditions should be further considered and explored.
authors.affiliation: Respiratory Department, Hospital de la Santa Creu i Sant Pau, and the Institute of Biomedical Research (IIB Sant Pau), Barcelona, Spain. Universitat Autònoma de Barcelona, Barcelona, Spain. jginer@santpau.cat.
authors.forename: Jordi
authors.initials: J
authors.lastname: Giner
authors.affiliation: Respiratory Department, Hospital de la Santa Creu i Sant Pau, and the Institute of Biomedical Research (IIB Sant Pau), Barcelona, Spain. Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Plaza
authors.affiliation: Research, Development, and Innovation Department, Sibel SA, Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Rigau
authors.affiliation: Clinical Epidemiology and Public Health Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Judit
authors.initials: J
authors.lastname: Solà
authors.affiliation: Universitat Autònoma de Barcelona, Barcelona, Spain. Clinical Epidemiology and Public Health Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain. Consorcio de Investigación Biomédica de Epidemiología y Salud Pública, Madrid, Spain.
authors.forename: Ignasi
authors.initials: I
authors.lastname: Bolíbar
authors.affiliation: Respiratory Department, Hospital de la Santa Creu i Sant Pau, and the Institute of Biomedical Research (IIB Sant Pau), Barcelona, Spain. Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Sanchis
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005541:Forced Expiratory Volume; D019983:Guideline Adherence / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D011446:Prospective Studies; D015203:Reproducibility of Results; D013147:Spirometry / Q000592:standards*; D014797:Vital Capacity
keywords: pulmonary function testing; quality control; spirometry; standards