Despite the widespread use of the bronchodilatator test in lung function testing, there is still disagreement on the clinical value of the methods of measurement and the quantitative criteria for assessment of the bronchodilatator response. A comparative analysis is made in the present study of five wide-known techniques of measuring bronchodilatator response (BDR) based on the change of FEV1.0 (delta FEV1.0) after administration of salbutamol in 20 patients with chronic bronchial asthma. An approach is proposed which uses the mean of predicted and initial values of FEV1.0 in the denominator. The results show that relating delta FEV1.0 to the mean of initial and predicted values of FEV1.0 (in the proposed method) or only to the initial value of FEV1.0 (in the method recommended lately by the European Respiratory Society) offers specific advantages for the analysis of bronchodilatator response which makes these methods worth trying in diagnostic practice.