Debate over the method used to identify students as learning disabled (LD) and in need of special education under the Individuals with Disabilities Education Act (IDEA) has gained considerable momentum during the last several years. A barrage of criticism has been directed at the “ability-achievement discrepancy” method of LD identification, which requires that students show a severe discrepancy between their IQ and academic achievement, through the use of standardized testing. This has resulted in intense interest in, and urgency for, finding alternative methods which could be both more timely and more reliable.

At the forefront of options being reviewed and researched is a process called “response-to-intervention” or RTI. A major study of RTI as an alternative method for LD identification is a significant portion of the work currently being conducted by the National Research Center on Learning Disabilities (NRCLD), a project of the U.S. Department of Education. This article briefly describes some criticisms of the “discrepancy” approach to evaluating a child for LD, and provides an overview of the RTI process.

The Debate Over LD Identification Procedures

Several issues have generated the debate about how to identify LD. First, there’s been an alarming increase in the numbers of students served in the LD category of IDEA. Of the 6 million children in special education, half of those are identified as having a “specific learning disability,” and the number has grown more than 300 percent since 1976. Policy makers have consistently expressed concern about the substantial number of students being served as LD under IDEA (now roughly 6 percent of all school-age children).

Second, a growing body of research suggests that the “ability-achievement discrepancy” method of identifying students as eligible for special education services requires students to fail or fall behind for a substantial period of time before they are eligible for help. This requirement for an “accumulation of failure” acts as a barrier to early help. Studies published by the National Institute of Child Health and Human Development also indicate that the further behind a student falls, the more intensive the services must be to help close the achievement gap.

There’s also sound evidence, in a study published by the National Research Council in 2002, that much of the testing used in this process is culturally biased, resulting in either too few or too many minority students being placed in certain categories of special education.

Features of the “Ability-achievement” Discrepancy Method

The ability-achievement discrepancy method dates back to 1977. When the U.S. Department of Education crafted the regulations to implement the Education for All Handicapped Children Act of 1975 (P.L. 94-142), now known as the Individuals with Disabilities Education Act (IDEA), it needed to provide a process and criteria for identifying students in the category of “specific learning disability.”

The process needed to differentiate between students who have low achievement because of low ability (as measured by IQ testing), and students whose low achievement is “unexpected” (those with normal or above normal ability, or IQ), and cannot be explained by other factors such as limited English proficiency.

To accomplish this, a requirement for the existence of a “severe discrepancy between achievement and intellectual ability” in one or more of seven domains of academic functioning was included in the final IDEA regulations.

To determine the existence of a “severe discrepancy,” states generally require the administration of standardized ability (IQ) tests and academic achievement tests, followed by a comparison of the standard scores of the tests. If this comparison shows that the student’s “achievement” is well below his or her “ability'” in at least one area (such as reading), then the student can be found eligible to receive special education services under the category of “specific learning disability.”

Defining Response-to-Intervention (RTI)

There is currently no formal definition of RTI, nor is there an RTI model that is well established and widely endorsed by researchers and educators. However, the following could serve as a description of the essential elements:

RTI is an individualized, comprehensive assessment and intervention process, utilizing a problem-solving framework to identify and address student academic difficulties using effective, efficient, research-based instruction.

How RTI Is Used to Identify a Student as Having LD

In an RTI process, students who show signs of learning difficulties are provided with a series of increasingly intensive, individualized interventions. These interventions are designed and delivered by general education staff in collaboration with other experts such as special educators and school psychologists and are based on reliable research. The intervention process includes systematic monitoring of the student’s progress. Students who do not show improvement, or a “response,” to this series of interventions are considered to be learning disabled and in need of special education services in order to receive educational benefit from instruction.

Some RTI models call for non-responsive students to also undergo individual comprehensive assessments prior to identification and eligibility for special education services. Such assessments may be used to identify the student’s strengths and weaknesses and to rule out other causes of the learning difficulties, such as mental retardation, behavioral disorders, or limited English proficiency.

Other RTI models don’t involve such assessments and rely solely on the intervention process as the diagnostic assessment for special education eligibility.

How RTI Differs from “Pre-referral Intervention”

A “pre-referral intervention” program is frequently used to provide some degree of differentiated instruction to a struggling student within the general education classroom. The interventions are designed and delivered by the student’s general education teacher prior to a referral for evaluation for special education, sometimes in consultation with other school staff. The process is designed to prevent inappropriate referrals to special education.

Several states have designed and implemented such pre-referral intervention programs, and some even require that such a program precede formal evaluation for special education. While a pre-referral intervention process could be viewed as the first “tier” or “stage” of a multi-level RTI process, such programs are not designed to be used as an LD identification process in and of themselves.

Some Benefits of RTI

Among the most notable benefits is that an RTI process will address the needs of low-achieving students quickly, providing individualized instruction that is research-based. This is particularly appealing in the area of early reading acquisition, where there is a wealth of research and an array of interventions based on that research.

Of course, RTI models are predicated on the expectation that all students are receiving high quality, research-based instruction in general education. If those conditions are in place for all students, reading research suggests that far fewer students will encounter difficulty learning to read. It is for this reason that programs created by the No Child Left Behind Act, such as Reading First, must include the essential components of reading instruction that have been identified through research.

Proponents of RTI also feel that data collected through such an intervention process will better inform instruction than do results of many of the assessments currently administered to determine the required “discrepancy” between a student’s IQ and achievement.

Some Disadvantages of RTI

Critics argue that a student’s lack of response to interventions is not adequate to identify the presence of learning disabilities. Such a process will identify students whose low achievement is the result of a variety of factors, such as mild retardation, limited English proficiency, language impairments, or deficits related to low socioeconomic status. However, only by employing individual comprehensive assessments can those with true learning disabilities be distinguished from those whose learning difficulties stem from other causes.

Additional concerns involve the difficulty of ensuring that the RTI process is implemented with integrity by well-trained staff who are knowledgeable about research-based interventions as well as procedures used to appropriately monitor student progress and performance. Today’s teaching conditions, including large class sizes, lack of adequate training, and strained school budgets, could make such implementation nothing more than a lofty but unrealistic goal for many schools across the country.

What the Future Holds for RTI

IDEA 2004 does not require schools to use the “discrepancy” approach to identify students with learning disabilities. However, it also does not prohibit its use. It also allows the use of RTI or some type of scientific, research-based intervention process to determine whether a student has learning disabilities and requires special education services. Just how this will change the current identification criteria and processes in place across the country remains to be seen.

If students can be provided with intensive, effective interventions at the earliest possible point in their school careers, it is highly likely that many will succeed without the need for special education. Since special education is a costly and frequently stigmatizing designation, efforts to enable student success without the need for special education should be wholeheartedly embraced.

A recent study of special education expenditures concluded that it is the rising number of special education students rather than the rising costs of serving those in special education that is creating greater and greater strain on school budgets. “Stemming the tide of special education enrollments appears to be the real answer to special education cost containment — a task that will require holistic education remedies and enhanced cooperation between regular and special educators,” the NRCLD researchers concluded. Effective implementation of any RTI process also depends on such cooperation and, without it, is doomed to fail.