Unreliability of maximum mid-expiratory flow rate as sole index of bronchodilator response in chronic asthma.

Analysis of individual patterns of response to bronchodilation in asthmatics, rather than group averages, emphasizes the varying types of "asthma" as well as the need to examine all parameters of lung function when evaluating any new therapeutic agent. The often praised maximum mid-expiratory flow rate may be very misleading as a parameter of drug response.