Spirometry quality-control strategies in a multinational study of the prevalence of chronic obstructive pulmonary disease.

UNLABELLED We report the characteristics of a centralized spirometry quality-control program developed for a population-based survey of the prevalence of chronic obstructive pulmonary disease in 5 cities: São Paulo, Brazil; México City, México; Montevideo, Uruguay; Santiago, Chile; and Caracas, Venezuela (the Latin American Project for the Investigation of Obstructive Lung Diseases [PLATINO]). METHODS We developed and used a 3-level quality-control system. Level 1: The spirometer used in the survey (EasyOne), gives quality-control messages to the user/clinician. All the spirometry technicians were trained by the same team, with the aim of meeting what became the 2005 spirometry quality criteria of the American Thoracic Society/European Respiratory Society (ATS/ERS). Level 2: In each of the 5 cities a local supervisor identified poor-quality spirometries that needed to be repeated. Level 3: Once a week during the survey, all spirometry results were sent via e-mail to the study's quality-control center in México City for review and feedback. RESULTS In the overall totals at the end of the study, 94% of the 5,315 subjects had spirometries that met the 1994 ATS quality criteria, and 89% met the 2005 ATS/ERS criteria. In their overall totals at the end of the study, 90% of the 64 spirometry technicians were successful in getting 86% of their subjects to meet the 1994 ATS criteria, and got 75% of their subjects to meet the 2005 ATS/ERS criteria. In the first 10 subjects they tested, 90% of the 64 spirometry technicians were successful in getting 70% of their subjects to meet the 1994 ATS criteria, and got 60% of their subjects to meet the 2005 ATS/ERS criteria. CONCLUSIONS Standardization of equipment, training, and supervision of spirometry is essential in a multinational spirometry survey. Centralized quality control can be done via e-mail with good reliability and low cost.