Response to Intervention and Severe Discrepancy Models
Many students in the special education system qualify for services because they have a specific learning disability that is impacting their progress in the general curriculum. Historically, a specific learning disability was diagnosed when a student had a severe discrepancy between his or her ability and achievement. However, since the reauthorization of the Individuals with Disabilities Education Act in 2004, Pennsylvania allows IEP Teams to use a response to intervention approach or a severe discrepancy approach to identify kids with specific learning disabilities.
Response to Intervention
In Pennsylvania, Response to Intervention (RTI) has two meanings. First, Response to intervention is a comprehensive strategy for identifying and helping students who might be at risk either academically or behaviorally. Second, Response to Intervention can be an alternative to the significant discrepancy model in identifying student with learning disabilities.
The RTI model uses research based interventions and strategies to help students. The student's response to those interventions and strategies should be well documented.
There are some basic components of Pennsylvania's RTI system that are important to note. First, all students should receive high quality research based instruction that is aligned with the general education standards and all students should be screened to see if they are meeting grade level expectations in both academics and behavior. Second, all staff in the school, including general education teachers, Title I teachers, ESL teachers etc, should be actively involved in assessment and instruction and the parents should receive accurate and frequent information about their children. Third, decisions about interventions and instruction should be based on data. Finally, the intervention system should be tiered so that students receive interventions based on their individual needs.
An IEP Team may decide that a student has a specific learning disability based on the student's response to interventions. A student who does not display an adequate rate of improvement to interventions and does not perform at grade level may be determined to have a specific learning disability.
Severe Discrepancy
Prior to the reauthorization of the federal Individuals with Disabilities Education Act (IDEA) in 2004, IEP Teams needed to find that a student had a severe discrepancy between intellectual ability and academic achievement and that the discrepancy was not due to other factors such as limited English proficiency or lack of instruction in order for that student to be considered to have a learning disability for purposes of special education. IEP Teams can still chose to use the severe discrepancy model if they wish.
The reason that the IDEA 2004 and its implementing regulations moved away from the severe discrepancy model is that it, by definition, the severe discrepancy model required Teams to wait until a student was having academic difficulties in order to find the child eligible for services. Conversely, the response to intervention model allows an IEP Team to find a student with a specific learning disability eligible for special education before he or she is having significant academic difficulties.