Shortcomings of the IQ-Based Construct of Underachievement

Despite being plagued by serious conceptual problems, underachievement ranks among the most popular constructs in research on the gifted. Many of its problems have their roots in the use of the IQ as the supposedly best method of measuring ability levels. Only a few decades ago the opinion was still widespread that the IQ-based construct of underachievement, having withstood neither its empirical nor its theoretical test, ought to be abandoned....