TY - JOUR T1 - Quality control of spirometry: a lesson from the BRONCUS trial JF - European Respiratory Journal JO - Eur Respir J SP - 1104 LP - 1109 DO - 10.1183/09031936.05.00026705 VL - 26 IS - 6 AU - R. Pellegrino AU - M. Decramer AU - C. P. O. van Schayck AU - P. N. R. Dekhuijzen AU - T. Troosters AU - C. van Herwaarden AU - D. Olivieri AU - M. Del Donno AU - W. De Backer AU - I. Lankhorst AU - A. Ardia Y1 - 2005/12/01 UR - http://erj.ersjournals.com/content/26/6/1104.abstract N2 - 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. ER -