In an insightful analysis of problems associated with SLD identification, Scruggs and Mastropieri (2002) offered criteria required for identification procedures to be deemed valid. These included:
- Does the identification procedure address the multifaceted nature of SLD?;
- Can the procedure be applied across the age spectrum of students with SLD?;
- Can the procedure be applied with measures demonstrating technical adequacy?;
- Will the procedure reduce overidentification of SLD?;
- Will the procedure reduce inappropriate variability in identification rates across state and local educational authorities?; and
- Will the procedure be more likely than current procedures to identify students who meet present conceptualizations of SLD?
Clearly, the RTI model does not yet meet these criteria. For example, the emphasis on phonological processing and the decoding aspect of reading fails to consider math, writing, or even reading comprehension deficits. The RTI emphasis on early identification and the avoidance of a "wait to fail" model would not appear to cross the age spectrum. Many measures associated with the RTI model are best viewed as "experimental" because their technical adequacy has not yet been established. The problem of overidentification will be difficult to resolve when the initial pool of students represents the lowest 25% (or even 30%) in reading achievement in a kindergarten or first-grade population. Across settings, the lowest 25% of the school population will likely show very different achievement distributions that are likely to produce very different numbers of non-responders. These different nonresponsiveness rates will do little to reduce the problem of variability across settings. Finally, many years of SLD research have contributed to the development of the SLD construct but the proposed RTI model captures only a single element associated with the basic psychological processing deficit definitional parameter (i.e., phonological processing deficits). Within the context of SLD identification, the possibility of a single processing deficit is too arcane, and it would take a significant conceptual leap to generalize this particular form of RD into SLD.
Scruggs and Mastropieri (2002) concluded their analysis by suggesting "that radically altering or eliminating the concept of learning disabilities because of problems with current identification procedures amounts to 'throwing the baby out with the bathwater'" (p. 165). The RTI model as presently described appears to radically alter the SLD concept and, consequently, cannot be endorsed; in fact, it will have the effect of eliminating much of what is known about SLD. At best, the RTI model identifies students who are at-risk for reading failure and who require intensive intervention to achieve any success. The narrowly focused reading achievement problem, the single processing deficit, and the limited intervention options suggest that what is being identified is a far cry from SLD in any significant sense. The disconnect between the RTI model and the SLD construct means that the number of false positives may theoretically be close to 100% while, at the same time, the number of false negatives may also be close to 100%. Such a scenario makes little sense but then neither does exclusively relying on RTI for SLD identification.