Ten Easy Ways to Estimate How Many Subjects You Need
In This Chapter
Quickly estimating sample size for several basic kinds of tests
Adjusting for different levels of power and alpha
Adjusting for unequal group sizes and for attrition during the study
Sample-size calculations tend to frighten researchers and send them running to the nearest statistician. But if you’re brainstorming a possible research project and you need a ballpark idea of how many subjects to enroll, you can use the ten quick and (fairly) easy rules of thumb in this chapter.
The first six sections tell you how many ...