Within-Groups Designs in Everyday Life We often use a within-groups design without even knowing it. A bride might use a within-groups design when she has all of her bridesmaids (the participants) try on several different possible dresses (the levels of the study). They would then choose the dress that is most flattering, on average, on the bridesmaids. We even have an innate understanding of order effects. A bride, for example, might ask her bridesmaids to try on the dress that she prefers either first or last (but not in the middle) so they’ll remember it better and be more likely to prefer it!

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