The first step in designing a study is to determine the comparisons to be made. The research design should be both internally and externally valid. In addition, it is important to know both the reliability and validity of the measurements made during the research. The research should also try to eliminate rater bias by preventing those who take the measurements from knowing which caliber of ammunition is being fired. Furthermore, statistical procedures should be selected carefully, with attention to influences of the sample size and the data variability. The analysis can include descriptive statistics, tests of the homogeneity of variance, analysis of variance, and post-hoc comparisons where significant differences are found. Finally, researchers must always keep in mind that the lives of law enforcement officers depend on the results. Photographs and footnote.