According to Flanagan et al. (2006), studies were identified for potential inclusion in their CHC COG-ACH summaries via three search methods. First, research studies that investigated the relations between cognitive abilities and reading, math, and writing achievement were identified via a search of the PsycINFO electronic database. Second, an ancestral search strategy of the references identified in step one revealed potentially useful other articles for review. Third, the original McGrew and Flanagan (1998) CHC COG- ACH summary table results were incorporated with the new-found research literature.
Studies deemed to have reported a significant COG-ACH relation by the Flanagan research group were then listed in tabular form in one of three categories: (a) key CHC studies—CHC- organized studies that included markers for most broad CHC cognitive abilities; (b) reviews—non- CHC organized narrative or meta-analytic research syntheses reporting significant relations between cognitive abilities and school achievement; and (c) individual studies—single non-CHC empirical studies that investigated the relations between cognitive abilities and school achievement. For most of the reviews and individual studies the Flanagan group translated the described non-CHC cognitive abilities as per the nomenclature of the CHC taxonomy (e.g., phonemic awareness = narrow ability of phonetic coding under the broad domain of Ga).
Flanagan et al.’s (2006) summary is impressive. A total of 138 references were presented for reading (8 key CHC studies; 23 reviews; 107 individual studies) and 37 references were presented for math (3 key CHC studies; 5 reviews; 29 individual studies).
In contrast, the Fiorello research group, in the process of promoting the use of CHC assessment in school neuropsychology practice (Fiorello & Primerano, 2005; Fiorello et al., 2006), reviewed many of the same key CHC-reading studies included in the Flanagan research group’s summary tables. The Fiorello group’s most important contribution was their “cross- walk” of neuropsychology research on reading disorders to the CHC framework. For example, Fiorello et al. (2006) related one component of the “double deficit” reading disability (rapid automatized naming or RAN; Wolf & Bowers, 1999) to CHC when they stated that “ideational fluency, together with Gs, is related to Rapid Automatized Naming” (p. 839). Since the Fiorello research group’s information was not based on an explicit research literature search and synthesis strategy, their interpretations are presented as supplemental to the more comprehensive Flanagan research group’s CHC COG-ACH synthesis efforts.
Stay tuned. The results of these prior research syntheses, as well as limitations of these syntheses will be posted next,followed by the description of the methods used to provide a more systematic and organized literature review (McGrew & Wendling, manuscript submitted for publication)
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