Single-Case Design in Education

Single-case experimental designs establish whether an intervention causes a change in behavior or learning by intensively studying individual cases over time rather than comparing groups. Each case serves as its own control: an outcome is measured repeatedly during a baseline phase and again under intervention, and the effect is demonstrated by replicating the change across phases or across cases. Central to special education and applied behavior analysis, and recognized by the What Works Clearinghouse and Horner and colleagues' standards, single-case design offers rigorous causal evidence when group experiments are impractical.