Quantitative meta-analysis of literature regarding the effectiveness of Direct Instruction (DI) curricular programs. DI is a highly structured curriculum first developed in the 1960s, expanded in subsequent years, and designed for a range of academic areas and student ages. The study authors examined 455 reports of DI's effectiveness published between 1966 and early in 2017. From these studies researchers calculated 4,643 effects, and also gathered detailed information on the studies including characteristics of the students, their schools, the length and quality of the intervention, characteristics of teachers, measures used to assess outcomes, and the research design. Data were gathered on both academic subjects and affective outcomes. Students ranged in age from pre-school to adult. Coders also noted potential methodological concerns with research design, measures, and analysis.
