Intelligence has been defined in multiple ways throughout history. In the last 100 years a psychometric approach to define the concept of intelligence has come to dominate the concept. This Commentary provides a brief overview of the history and concepts of intelligence with an emphasis on intellectual assessment. Particular focus is placed on the…

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…