Future studies of overactive bladder: the need for standardization.

Clinicians and researchers agree that pharmacologic studies of the overactive bladder (OAB) require precise planning, strict adherence to study design, and meticulous attention to study conduct and statistical methods. In addition, there should be straightforward and highly directed formulation of the conclusions derived expressly from data that have been collected. The exact methods to achieve these ends, however, are often debated among statisticians and experts in study design and by physicians who interpret the clinical implications of the findings. For these reasons, the conclusions of clinical research in OAB are commonly criticized on the basis of study objectives, study design, statistical methods, or conclusions. However, a subtler, but possibly more critical problem exists: the method of defining the population and the methods for collecting the data for the efficacy outcome parameters, including frequency, urgency, and urge incontinence.