title: Quality control of spirometry: a lesson from the BRONCUS trial.
abstract: This report describes the quality control programme used within the Bronchitis Randomized on N-acetylcysteine (NAC) Cost-Utility Study, a trial designed to assess the decline in lung function, exacerbation rate, health status, and cost-effectiveness with NAC or a placebo in 523 patients with chronic obstructive pulmonary disease over a 3-yr period. Spirometry was scored from 0 (worst quality) to 6 (best quality). The mean score of 314 spirometries from 243 patients evaluated during the trial was 5.63+/-0.83. Linear regression analysis of the scores of 47 participating centres plotted against the time at which spirometries were performed yielded an intercept of 5.7+/-0.5 and a slope of -0.0001+/-0.001, which suggests that the initial high quality was maintained over time. Retrospective examination of a further 345 postbronchodilator spirometries from 208 patients with a forced expiratory volume at one second exceeding the mean individual value recorded over the study in excess of 20% revealed a slightly lower quality of the start-of-test manoeuvre compared with the 314 spirometries. In conclusion, these findings would suggest that the quality control programme is likely to have helped achieve and maintain long-term spirometry performance in the Bronchitis Randomized on N-acetylcysteine (NAC) Cost-Utility Study trial. Special care should be paid to the spirometries whose forced expiratory volume in one second values exceed the mean value.
authors.affiliation: Centro di Fisiopatologia Respiratoria e di Studio della Dispnea, Azienda Ospedaliera S. Croce e Carle, 12100 Cuneo, Italy. pellegrino.r@ospedale.cuneo.it
authors.forename: R
authors.initials: R
authors.lastname: Pellegrino
authors.forename: M
authors.initials: M
authors.lastname: Decramer
authors.forename: C P O
authors.initials: CP
authors.lastname: van Schayck
authors.forename: P N R
authors.initials: PN
authors.lastname: Dekhuijzen
authors.forename: T
authors.initials: T
authors.lastname: Troosters
authors.forename: C
authors.initials: C
authors.lastname: van Herwaarden
authors.forename: D
authors.initials: D
authors.lastname: Olivieri
authors.forename: M
authors.initials: M
authors.lastname: Del Donno
authors.forename: W
authors.initials: W
authors.lastname: De Backer
authors.forename: I
authors.initials: I
authors.lastname: Lankhorst
authors.forename: A
authors.initials: A
authors.lastname: Ardia
mesh_terms: D000111:Acetylcysteine / Q000627:therapeutic use*; D000368:Aged; D018450:Disease Progression; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000188:drug therapy*; D011786:Quality Control; D012016:Reference Values; D012129:Respiratory Function Tests; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013147:Spirometry / Q000379:methods*
chemical_list: D000111:Acetylcysteine