Calidad de las espirometrías en un estudio epidemiológico de terreno: Factores determinantes de la necesidad de repetir el examen en el estudio Platino-Chile

Abstract

Spirometry, the most used test to evaluate pulmonary function, is only occasionally measured in field epidemiological studies. Our aim was to determine which of the following factors in the Platino study can be associated low quality spirometries in the first session: sex, age, socioeconomic level, educational level, body mass index, cold chill, smoking, operating technician, date and subject's previous spirometric experience. 1.168 individuals were evaluated with spirometry. Fifteen nurses and 1 midwife were trained according to NIOSCH standards. Easy One NDD spirometers were used. 1.037 subjects (88.8%) performed a satisfactory spirometry in the first session, and 131 (11.2%) failed to do so. Only two significant predictors of this failure were identified: age and educational level. Causes for test repetition were 1) Non satisfactory acceptability (77.1%); 2) lack of reproducibility (67.9%); 3) decline of post bronchodilator CVF without concomitant change in VEF1 (36.6%). Eighty nine of the 131 subjects accepted to repeat the test. A satisfactory spirometry was obtained in 79 subjects. Hence, at the end of the study 95.5 % of the subjects attained a satisfactory test. We conclude that personnel without experience, with appropriate training, can perform high quality field spirometries. Acceptability and repoducibility were the most sensitive factors associated with a bad performance of spirometry. Age and schooling were the main factors related with a low quality spirometry. No association was detected regarding technician as a predictor of low quality spirometries carried out in a population setting