Sample size refers to the number of subjects in a study. If there is only one sample, then the sample size is designated with the letter “N.” If there are samples of multiple populations, then each sample size is designated with the letter “n.” When there are multiple population samples, then the [Page 1300]total sample size of all samples combined is designated by the letter “N.”

A study's sample size, or the number of participants or subjects to include in a study, is a crucial aspect of an experimental design. Running a study with too small of a sample runs numerous risks including not accurately reflecting the population a sample was drawn from, failing to find a real effect because of inadequate statistical power, and finding ...