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.

The long-term stability of portable spirometers used in a multinational study of the prevalence of chronic obstructive pulmonary disease.

BACKGROUND: We report the performance of an ultrasound-based portable spirometer (EasyOne) used in a population-based survey of the prevalence of chronic obstructive pulmonary disease, conducted in 5 Latin American cities: São Paulo, Brazil; México City, México; Montevideo, Uruguay; Santiago, Chile; and Caracas, Venezuela (the Latin American COPD Prevalence Study [PLATINO]). METHODS: During the survey period (which ranged from 3 months to 6 months in the various locations) we collected daily calibration data from the 70 EasyOne spirometers used in the 5 survey cities. The calibrations were conducted with a 3-L syringe, and the calibration data were stored in the spirometer's database. RESULTS: Ninety-seven percent of the calibration volumes were within +/- 64 mL (2.1%) of the 3-L calibration signal. Excluding data from the first city studied (São Paulo), where one calibration syringe had to be replaced, 98% of the calibration checks were within +/- 50 mL (1.7%). The measured volume was affected only minimally by the syringe's peak flow or emptying time. CONCLUSION: In these 70 EasyOne spirometers neither calibration nor linearity changed during the study. Such calibration stability is a valuable feature in spirometry surveys and in the clinical setting.

[Spirometric reference values in 5 large Latin American cities for subjects aged 40 years or over]. / Valores de referencia espirométrica en 5 grandes ciudades de Latinoamérica para sujetos de 40 o más años de edad.

OBJECTIVE: In clinical practice, spirometry is a extremely useful test that requires strict quality control, an appropriate strategy for interpretation, and reliable reference values. The aim of this study was to report spirometric reference values for 5 cities in Latin America. PATIENTS AND METHODS: From data for 5315 subjects who had undergone spirometry in the PLATINO study in Caracas, Mexico City, Santiago, São Paulo, and Montevideo, we selected information for 906 (17%) individuals aged between 40 years and 90 years to provide reference values. The chosen subjects had never smoked, were asymptomatic, had not been diagnosed with lung disease, and were not obese. Multiple regression models were constructed with the following spirometric parameters: forced expiratory volume in 1 second (FEV1) and in 6 seconds (FEV6), peak expiratory flow, forced vital capacity (FVC), FEV1/FEV6, FEV1/FVC, and forced midexpiratory flow rate. Height, sex, and age were also included in the model. RESULTS: Average values for the subjects studied were similar to those for the white North American population and the Mexican-American population of the third National Health and Nutrition Examination Survey, but exceeded those of the black population of the same survey by 20%. CONCLUSIONS: The proposed reference values are an improvement on those currently available for Latin America because the participants were chosen by population sampling methods and standardized up-to-date methodology was used.

Valores de referencia espirométrica en 5 grandes ciudades de Latinoamérica para sujetos de 40 o más años de edad / Spirometric reference values in 5 large Latin American Cities for subjects aged 40 years or over

Objetivo: La espirometría es una prueba de gran utilidad clínica, que requiere un estricto control de calidad, una estrategia de interpretación y valores de referencia adecuados. El propósito del presente trabajo es comunicar los valores de referencia para la espirometría en 5 ciudades de Latinoamérica. Pacientes y métodos: El estudio PLATINO se llevó a cabo en Caracas, México, Santiago, São Paulo y Montevideo e incluyó a un total de 5.315 sujetos con espirometría realizada. De ellos, se estudió a 906 (17%) que tenían entre 40 y 90 años de edad para crear valores de referencia, porque nunca habían fumado, estaban asintomáticos y no tenían enfermedad pulmonar diagnosticada ni obesidad. Se efectuaron modelos de regresión múltiple con los valores espirométricos --volumen espiratorio forzado en el primer segundo (FEV1) y en 6 s (FEV6), flujo espiratorio máximo, capacidad vital forzada (FVC), FEV1/FEV6, FEV1/FVC y flujo mesoespiratorio forzado--, la talla, el sexo y la edad. Resultados: Los sujetos estudiados presentaron en promedio valores similares a los de la población norteamericana blanca y americana de origen mexicano del estudio NHANES III, pero superiores a los de la población negra en un 20%. Conclusiones: Los valores de referencia propuestos representan una ventaja sobre los disponibles en la actualidad en Latinoamérica, ya que se eligió a los participantes por métodos de muestreo poblacional y el método empleado es estandarizado y actualizado

Objective: In clinical practice, spirometry is a extremely useful test that requires strict quality control, an appropriate strategy for interpretation, and reliable reference values. The aim of this study was to report spirometric reference values for 5 cities in Latin America. Patients and methods: From data for 5315 subjects who had undergone spirometry in the PLATINO study in Caracas, Mexico City, Santiago, São Paulo, and Montevideo, we selected information for 906 (17%) individuals aged between 40 years and 90 years to provide reference values. The chosen subjects had never smoked, were asymptomatic, had not been diagnosed with lung disease, and were not obese. Multiple regression models were constructed with the following spirometric parameters: forced expiratory volume in 1 second (FEV1) and in 6 seconds (FEV6), peak expiratory flow, forced vital capacity (FVC), FEV1/FEV6, FEV1/FVC, and forced midexpiratory flow rate. Height, sex, and age were also included in the model. Results: Average values for the subjects studied were similar to those for the white North American population and the Mexican-American population of the third National Health and Nutrition Examination Survey, but exceeded those of the black population of the same survey by 20%. Conclusions: The proposed reference values are an improvement on those currently available for Latin America because the participants were chosen by population sampling methods and standardized up-to-date methodology was used