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 Within-subject designs use a single group of participants and test each individual in all different treatments being compared. The primary disadvantage of within-subjects designs is that they can result in order effects. An order effect occurs when participants' responses in the various conditions are affected by the order of conditions to which they were exposed. Some of the problems associated are fatigue, boredom, or practice effects. So to minimize it, fatigue effects can be reduced by shortening the procedures and making the task more interesting, boredom can also be reduced by providing breaks during the experiment. These breaks help the participants feel fresh and not bored, and also help in recovering from an adaptation from the previous experiment, and practice effects can be reduced by providing a warm-up exercise before the experiment begins.