Single-case research involves an experimental approach to answering the question: Is there an effect? Questions of causal inquiry can be answered using randomized control trials (RCTs), regression discontinuity designs, as well as single-case research designs (SCRDs). This entry focuses on SCRDs, which enables researchers and practitioners to determine whether a strategy, practice, or program (independent variable—x) impacts a given behavior (dependent variable—y). For example, one may want to determine whether incorporating instructional choices during writing instruction (x) increases student engagement (y) for four middle school students. This question can be answered using an SCRD. A common misconception is that single-case research is the same as case studies (which are not experimental designs). This is simply not correct.

SCRD can be a highly effective approach for examining ...