title: Reduction of pulmonary function indices: comparison of two hierarchical methods.
abstract: From tests for evaluating pulmonary function many indices may be calculated. In order to reduce their redundancy, two hierarchical methods for selecting the most significant indices are applied to data collected on a group of 228 firemen. The first method consists in a stepwise linear discriminant analysis which selects the indices according to their discriminant value for distinguishing between asymptomatic and symptomatic subjects. The second one is derived from a stepwise multiple correlation procedure, which selects the indices on the basis of their linear relationships. These two methods lead to different results and the choice between them should be made according to the aims intended for data reduction.
mesh_terms: D000328:Adult; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012129:Respiratory Function Tests / Q000379:methods*; D013223:Statistics as Topic; D014797:Vital Capacity