Abstract This chapter evaluates the results of a randomized trial conducted to test the effectiveness of an experimental treatment in slowing the pathological changes in memory caused by Alzheimer's disease. Individuals with Alzheimer's disease were randomly divided into two groups. One group received a placebo (twenty-six patients), and the other received a treatment of lecithin (twenty-five patients). Comparison of “before” and “after”measures of memory among Alzheimer's disease patients indicates an important difference between the patients who received lecithin and the patients who received a placebo. Four statistical approaches (t-test, Wilcoxon, bootstrap, and randomization procedures) yield the same inference: the lecithin patients appear to have significantly less deterioration.