Statistics current clinical trials

The previous chapter discussed the (currently) relatively loosely defined statistical approaches to safety data collected in clinical trials. In contrast, there are widely accepted statistical methods for demonstrating efficacy in clinical trials. As has been noted several times in this book, if the study design and methodology have been appropriate and have led to the collection of optimum quality data, the statistical analysis and interpretation of efficacy data are relatively straightforward. The clinical (biological) interpretation of efficacy data is typically not quite as clear-cut, but there are widely accepted methodologies that are very useful in this realm too. Of particular importance here is the expert judgment of the clinicians who will review the statistical results with the statisticians and the rest of the study team. 

The newer serotonin receptor agonists and antagonists tegaserod and alosetron act on Gl-specific serotonin receptors to treat constipation-predominant and diarrhea-predominant IBS, respectively. However, both drugs are currently only indicated for women. Efficacy and safety in men has not been established because the initial manufacturer s sponsored clinical trials contained insufficient numbers of men with IBS to provide the necessary statistical power to prove efficacy and safety. Ongoing studies should determine if these drugs are indicated in men. 

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