Single case designs (SCDs) and randomized small group (RSG) designs are two options for researchers who have limited resources and who would like to demonstrate the experimental effect of an intervention. The authors address considerations for internal and external validity in each design and provide an overview of the strengths and limitations of the various statistical analyses in each design. Effective researchers are well-informed regarding research design and match small-n participant designs to appropriate research questions. Examples of research questions and research design are discussed.
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