CattellHornCarroll abilities and cognitive tests: What we've learned from 20 years of research

This article reviews factor-analytic research on individually administered intelligence tests from a Cattell–Horn–Carroll (CHC) perspective. Although most new and revised tests of intelligence are based, at least in part, on CHC theory, earlier versions generally were not. Our review suggests that whether or not they were based on CHC theory, the factors derived from both new and previous versions of most tests are well explained by the theory. Especially useful for understanding the theory and tests are cross-battery analyses using multiple measures from multiple instruments. There are issues that need further explanation, of course, about CHC theory and tests derived from that theory. We address a few of these issues including those related to comprehension–knowledge (Gc) and memory factors, as well as issues related to factor retention in factor analysis. C © 2010 Wiley Periodicals, Inc.