Beyond g: The impact of Gf-Gc specific cognitive abilities research on the future use and interpretation of intelligence tests in the schools

This article describes recent developments in intelligence theory, applied measurement, and research methodology that suggest that new research is needed to reexamine the relative importance of both general and specific cognitive abilities in explaining school achievement. A summary of the results of a set of studies which examined the relationship between g and seven Gf-Ge specific abilities and general and specific reading and mathematics skills, is presented. These studies were designed to reexamine the g versus specific abilities issue in a manner that reflects progress in theory, measurement, and methodology. Analyses were conducted in separate model calibration and cross-validation samples (n = 222 to 255) at each of five grade levels (i.e., grades 1-2, 3-4, 5-6, 7-9, and 10-12). These studies used structural equation modeling procedures and tests from a validated Gf-Ge organized intelligence battery to operationalize a hierarchical g + Gf-Gc model consistent with Carroll's (1993) three stratum model of intelligence. Across all analyses, the relationship of g to general reading and math was as expected - significant and strong across all developmental levels. However, a number of significant and strong cross-validated direct effects for specific Gf-Ge abilities on specific reading and math skills also were found. The results of these studies suggest that (a) some specific abilities, including auditory processing, and fluid and crystallized intelligence, may be important for understanding the development of specific reading and math skills, above and beyond the understanding gained from general cognitive (g) and achievement constructs; (b) the predominate ''Just say no'' to subtest analysis position presented in much of the school psychology literature may need to be reevaluated; and (c) practitioners need to broaden their assessments beyond traditional instruments (e.g., Wechsler, 1991), in order to measure specific cognitive abilities that maybe important in the development of specific reading and math skills.