Identifying students with learning disabilities is crucial for providing appropriate support and resources. Two primary options exist: the traditional IQ-achievement discrepancy model and the more recent Response to Intervention (RTI) approach. This article will explore both, outlining their key features and differences.
The IQ-Achievement Discrepancy Model
This model compares a student’s intellectual ability (IQ) with their academic achievement. A significant discrepancy between a high IQ and low achievement in areas like reading or math suggests a learning disability. This model relies heavily on standardized tests to measure both IQ and achievement. A certified diagnostician or school psychologist typically administers these tests. The primary purpose is to rule out low intellectual ability as the cause of academic struggles.
The Response-to-Intervention (RTI) Approach
RTI focuses on providing early and intensive intervention to struggling learners. It operates on the principle that inadequate instruction, rather than an inherent disability, might be the root of academic difficulties.
RTI is a multi-tiered system:
- Tier 1: All students receive high-quality, research-validated instruction in the general education classroom. Progress is monitored regularly, often weekly.
- Tier 2: Students who don’t respond adequately to Tier 1 instruction receive more targeted support, often in small groups, with differentiated instruction or supplemental materials. Progress monitoring continues.
- Tier 3: Students who still struggle in Tier 2 receive even more intensive, individualized interventions. This may involve specialized instruction from a specialist. If progress remains insufficient, a comprehensive evaluation for a learning disability might be recommended. Data collected throughout the RTI process informs instructional decisions and can contribute to the identification of a learning disability. Primarily, general education teachers or other intervention specialists gather this data.
Comparing the Two Approaches
The table below summarizes the key differences between the IQ-achievement discrepancy model and the RTI approach:
| Feature | IQ-Achievement Discrepancy Model | Response to Intervention (RTI) |
|---|---|---|
| Purpose | Rule out low IQ as the cause of learning difficulties | Rule out inadequate instruction as the cause of learning difficulties |
| Target Population | Students suspected of having learning disabilities | All struggling learners, including those suspected of having learning disabilities |
| Process | Standardized testing to identify discrepancies between IQ and achievement | Ongoing monitoring of student performance and increasingly intensive interventions |
| Data Used | IQ and achievement test scores | Data from frequent progress monitoring, potentially including standardized test scores |
| Data Collector | Certified diagnostician or school psychologist | General education teacher or intervention specialist |
Conclusion
Both the IQ-achievement discrepancy model and the RTI approach serve as valuable tools for identifying students with learning disabilities. The IQ-achievement discrepancy model offers a more direct assessment of cognitive abilities and academic skills, while RTI emphasizes early intervention and data-driven instruction. While some states or districts might prefer one model over the other, both can contribute to a comprehensive understanding of a student’s learning needs and help ensure they receive the necessary support to succeed. The choice between the two often depends on specific state or district regulations and the individual needs of the student.
