Special education has a long tradition of valuing a continuum of placements and services to meet individual students' needs (Deno 1970). The alignment with response to intervention (RTI) and the provision of evidence-based intervention is strong. In this chapter, we discuss the research base and characteristics of RTI as they relate to students with learning disabilities (LD) and special education services in general. We discuss RTI as both a system of educational service delivery as well as a method for determining eligibility for special education services as a student with LD. Both definitions and approaches are important to examining the intersection of RTI and special education and there is a good amount of overlap.The authors begin this chapter with definitions of some of the key terms that are important to the treatment of the topic throughout the rest of the chapter. Next, the research base in relation to some key components of RTI and how they link to the needs of students with LD and the provision of special education services are presented. These include (a) eligibility and exit determinations, (b) tiered delivery of services, (c) evidencebased practices (EBPs), (d) universal screening, and (e) progress monitoring. Finally, some directions for future research in this area that are derived from prior research and gaps therein as well as implications of the current research base for the implementation of RTI are provided.
Definitions• Aptitude-achievement discrepancy: A method for identifying students with LD. It includes comparing a student's performance on a standardized, norm-referenced achievement test to a test of cognitive ability. A student is determined to have a LD if his/her achievement score is less than would be predicted given his/her cognitive ability. The RTI framework can be used as an alternative method for identifying students with LD.• Child Find: A federal mandate that requires school districts to locate, identify, and evaluate children with disabilities, from birth to age 21, to ensure provision of a free and appropriate public education through special education and/or related services.• Curriculum-based measurement (CBM): A measurement system which uses instruments and metrics highly associated with the curriculum a student is expected to learn. Thus, little inference is required regarding the determination of students' skill level.• Evidence-based practices (EBPs): Instructional practices that are supported by high-