Experimental Intervention Research Research Articles

Research to Practice (and Back Again) in Speech-Language Intervention

Three theses are developed in this article. First, although they share the common goal of striving toward the best intervention services possible, clinical practice and experimental intervention research are different in fundamental and practically significant ways. Second, nonexperimental research, some of which can be implemented by clinicians, provides an essential bridge between experimental investigation and clinical application. Third, professional and academic bodies governing speech-language pathology must take steps to ensure that speech-language professionals in research and clinical practice work in a complementary manner to develop and test the most effective intervention methods possible.

Experimental Intervention Research on Students with Learning Disabilities: A Meta-Analysis of Treatment Outcomes

This article summarizes a comprehensive synthesis of experimental intervention studies that have included students with learning disabilities. Effect sizes for 180 intervention studies were analyzed across instructional domains, sample characteristics, intervention parameters, methodological procedures, and article characteristics. The overall mean effect size of instructional intervention was positive and of high magnitude (M = 0.79). Effect sizes were more positive for a combined model that included components of direct and strategy instruction than for competing models. Interventions that included instructional components related to controlling task difficulty, small interactive groups, and directed responses and questioning of students were significant predictors of effect size, and interventions that varied from control conditions in terms of setting, teacher, and number of instructional steps yielded larger effect sizes than studies that failed to control for such variations. The results are supportive of the pervasive influence of cognitive strategy and direct instruction models for remediating the academic difficulties for children with learning disabilities.