CHC intelligence testing in the context of "Response to Intervention" (RtI) models
The impact of theRtI movement on the assessment activities of school psychologists is in its formative stage. Will RtI supplant traditional cognitive ability testing, supplement it in a complimentary manner, or be a short-term blip on the school psychology radar screen that fades away? We believe that RtI and cognitive ability testing have the potential to form a powerful assessment-intervention monitoring dyad. However, we also believe cognitive ability testing practices need to become more purpose-driven, flexible, and selective.
The identification of a psychological process disorderfor SLD classification requires some form of cognitive assessment (Newton & McGrew, 2009). We believe less emphasis should be placed on the overall full scale IQ and that cognitive assessment should be more selective and focused. For example, there should be selective testing of key markers for screening “at risk” children. Researchers advocating early screening as an integral component of some RtI models have identified many abilities (e.g., phonemic awareness; working memory; speed of lexical access or rapid automatic naming speed, vocabulary, etc.) which are measured by a number of contemporary intelligence batteries. Given that the major intelligence testing batteries are among the most psychometrically sound and well standardized tools available to school psychologists, it makes sense that these tests be used for measurement of “at risk markers” in lieu of  less technically sound special-purpose instruments. Additionally, treatment resistors will likely need a traditional comprehensive assessment of cognitive strengths and weaknesses as part of the evaluation process for diagnosis and eligibility determination as well as to facilitate intervention planning.
The CHC taxonomy of cognitive abilities is the consensus framework from which cognitive abilities are now most often conceptualized and measured (McGrew, 2009). Thus, a critical question is “what CHC broad or narrow cognitive abilities hold promise either as early screening markers or collectively as pattern indicators of a potential SLD process disorder?”  Answers to this question reside in the CHC cognitive-achievement relations (CHC COG-ACH) research completed over the past twenty years.  It is time to take stock and determine which, if any, CHC cognitive constructs and measures should be included in  the school psychologist’s assessment arsenal in a new hybrid approach to assessment and intervention—one that combines information from RtI and purpose-driven cognitive ability testing.