Between Subjects Design
In a Between Subjects Design each participant participates in one and only one group. The results from each group are then compared to each other to examine differences, and thus, effect of the IV. For example, in a study examining the effect of Bayer aspirin vs Tylenol on headaches, we can have 2 groups (those getting Bayer and those getting Tylenol). Participants get either Bayer OR Tylenol, but they do NOT get both.