Excerpt

In this issue, Chiuzan et al1 present the most commonly applied methods for the calculation of sample size in clinical studies. Sample size estimation is an important, and often, overlooked component of all study designs. Grant agencies and other funding sources as well as scientific journals expect that appropriate sample size calculations have been performed, and that they are described in grant applications or scientific manuscripts. This will frequently involve collaboration with a statistician, but for simple and straightforward study designs, investigators may be able to perform these themselves, as outlined by Chiuzan et al.1 The ability to do this saves time and cost in the study design period. Regardless, even if an investigator plans to consult with a statistician, some basic understanding by the investigator of the requirements for appropriate sample size calculation will make the process considerably more efficient and less costly, saving time and money. …