Interaction between Early Intervention Curricula and Student Characteristics

This study examined the relative effects of two highly contrasting early intervention programs, Mediated Learning (ML) and Direct Instruction (DI), in a randomized design. Subjects were children (ages 3–7 years) with mild to moderate disabilities in cognitive, language, socioemotional, and motor development. No main effect differences between the two groups were found on a battery of cognitive, language, and motor measures. Aptitude-x-Treatment Interaction (ATI) analyses of pretest and posttest results indicated that, contrary to conventional wisdom, relatively higher performing students gained more from DI, whereas relatively lower performing students gained more from ML. Although ATIs were significant, the effect sizes were modest (3%-8% of variance) and do not yet warrant major changes in educational practices