What does the neuropsychological category test measure?

The Halstead Category Test of brain dysfunction is one of the most sensitive neuropsychological measures currently available. While the instrument has received widespread use, nevertheless, the exact nature of what it measures has been poorly delineated. The present brief report presents the results of separate factor analyses of the Category Test along with other neuropsychological measures from the Halstead-Reitan battery. Despite considerable differences in samples, as well as in the particular neuropsychological measures included in the separate analyses, the Category Test consistently lined-up with general intellectual and memory components, in each instance.