The bronchodilator test in chronic obstructive pulmonary disease: interpretation methods.
The objective of the study was to evaluate the best method for interpreting the bronchodilator test (BDT). Five formulas for expressing the BDT results were analyzed and compared: changes experienced by maximum expiratory volume in 1s (FEV(1)) and forced vital capacity (FVC) measured in milliliters, in percentage with respect to the baseline, in percentage with respect to the predicted, in percentage with respect to the possible, and in standardized residuals. Ninety-eight chronic obstructive pulmonary disease (COPD) patients were submitted to a respiratory function test on two different days. On each occasion three spirometries were conducted: basal, post-placebo and post bronchodilator. As a gold standard, a normality interval was defined using the variability experienced with the placebo between the two days of the study. The best formulas according to their sensitivity, specivity and area under receiver operating characteristic (ROC) curve were the "standardized residuals", with a cut point of .3, and the "percentage with respect to the predicted" with a cut point of 6%.
Rodríguez-Carballeira
M
M
Department of Internal Medicine, Hospital Mútua de Terrassa, Plaza Dr Robert, 5, 08221 Terrassa, Barcelona, Spain. 27630mrc@comb.es
Heredia
J L
JL
Rué
M
M
Quintana
S
S
Almagro
P
P
D000368:Aged; D001985:Bronchial Provocation Tests; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D003627:Data Interpretation, Statistical; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013147:Spirometry; D013726:Terbutaline / Q000627:therapeutic use*; D016896:Treatment Outcome; D014797:Vital Capacity
D001993:Bronchodilator Agents; D010919:Placebos; D013726:Terbutaline