Just How Effective is Direct Instruction?

Despite overwhelming evidence in support of Direct Instruction, this research-validated curriculum has not been widely embraced by teachers or school administrators. The Direct Instruction model, developed and refined by Engelmann and colleagues over the past 50 years, has been the focus of numerous research studies, systematic reviews, and meta-analyses. Although its efficacy cannot be doubted, the significance of Direct Instruction's impact may be misunderstood. We attempt to clarify the importance of Direct Instruction with help from the binomial effect-size display. Binomial effect-size displays allow for intuitive and informative data-based decision making by clearly conveying the real-world importance of treatment outcomes through a juxtaposition of the relative proportions of success. The limitations of analyzing effect sizes in absolute terms are discussed. Using the binomial effect-size display as a framework, we present a series of dichotomies in an attempt to answer the question: Just how effective is Direct Instruction? © Association for Behavior Analysis International 2021.