ABSTRACT
This chapter discusses single-case designs that can be used for identifying evidence-based practices for an individual student, group of students, classrooms, and schools in a research program focused on the implementation processes of an intervention. Single-case methodology is in the tradition of quasi-experimental time-series designs but represents an improvement in causal inference in that replication of the intervention is scheduled as part of the design structure. The large evidence base from single-case research in special education and clinical and school psychology was discounted by the What Works Clearinghouse for not contributing to scientifically supported practices. The three major single-case designs are ABAB designs, alternating treatment designs, and multiple-baseline designs. The chapter also presents recent advances in single-case design studies to increase both the quality and scientific rigor for conducting intervention research and for identifying intervention components that are either working or impeding effective implementation.
