“…Others advocate even greater prudence, noting further research is necessary before RTI can be implemented as an identification technique with any degree of fidelity or validity (e.g., Fuchs & Fuchs, 2006; NJCLD, 2005). Particular areas of focus for future research include creating a common language for defining at–risk status and non–responsiveness, as well as valid measures for categorization (e.g., Fuchs, 2003; Gersten & Dimino, 2006; McMaster et al, 2005), conducting cost analyses (e.g., Gresham, 2001), exploring RTI applications to higher grades or academic areas outside of reading (e.g., King–Sears et al, 2004; Mellard, Byrd, et al, 2004), and delineating procedures for ensuring intervention fidelity and consistency of identification practices across schools, districts, and states (e.g., Mastropieri & Scruggs, 2005). An additional area of concern is teacher quality, for lack of responsiveness is not independent of a teacher's performance (e.g., Gerber, 2005).…”