OPTIMAL COMBINATIONS OF LUNG-FUNCTION TESTS IN THE DETECTION OF VARIOUS TYPES OF EARLY LUNG-DISEASE

  • 1 October 1987
    • journal article
    • research article
    • Vol. 71  (4) , 273-285
Abstract
The ability to detect early lung disease with different combinations of lung function tests was assessed by discriminant analysis. A number of lung function tests were performed in 224 never-smokers, 232 smokers, 111 pneumoconiotic subjects and 137 asthmatic patients. The discriminatory capacities of different combinations of test variables are presented. For detecting lung damage induced by tobacco smoke, a combination of the transfer factor and the slope of the alveolar plateau (phase III) increased the sensitivity from 18% to 32% at a specificity of 95%, compared with phase III alone. Dynamic spirometry did not add to the discriminatory capacity. Patients with asthma could be separated from reference subjects by airway resistance, Phase III or a combination of variables in dynamic spirometry. Pneumoconiotic subjects were best identified by a combination of the transfer factor, volumic compliance and phase III. Closing capacity divided by total lung capacity (TLC) and FEV1/TLC further improved the discrimination between different subgroups.