Considerations for Peptic Ulcer Trials

Abstract

A drug trial concerned with peptic ulcer treatment bas to be carefully planned to make possible a valid conclusion.

Calculations of the number of patients reguired have to be made early. This depends upon factors such as: a) if the comparison is to be made between two active drugs or an active drug and a placebo, b) if the aim is to show that two treatments are almost equal or if a certain difference is expected, c) the number of groups to be compared, and d) if intermediate checks are to be made. Thus, from a few dozen patients up to several thousand may be needed.

if a multicenter desing is adopted, which is often nessesary, the minimum number of patients required from each centre should be specified and a good reporting system has to be created.

When presenting the results, it is preferable to calculate a confidence interval for the difference between the treatments — especially in small studies where the risk is false conclusions would otherwise be large.

Key Words:

• clinical trials
• confidence interval
• null hypothesis
• statistical analysis
• sample size