Analysis of Maximal Expiratory Flow-Volume Curves. Visual Evaluation and Quantitative Evaluation.

Abstract

Maximal expiratory flow-volume (MEFV) curves have been utilized in the diagnosis of chronic obstructive lung diseases, in the survey of air pollution, and in studies of respiratory functions in school children. Indices for the lower lung volumes of MEFV curves have been used in statistical analysis or individual evaluation because of their effort independence, while indices for higher lung volumes of MEFV curves, which were considered to be effort-dependent, have not been used. A few reports using indices for higher and lower lung volumes have been described because the indices for higher lung volumes are as reproducible to the maximal expiration as those for lower lung volumes. Recently, MEFV-type analysis has been studied and this analysis has been useful in assessing the effects of smoking on MEFV curves, or in assessing subjects with nasal allergies or those with prior nasal allergies. From the aspects of hygiene, this review mainly describes MEFV-type analysis and the quantitative analysis of discriminant analysis.