Radex structure of Jacksonʹs Basic Personality Inventory

The sub-scale structure of Jacksonʹs Basic Personality Inventory (Jackson, Manual for the Basic Personality Inventory, 1989) has been explored in a number of different investigations. The chief conclusions are that: 1. (1) the sub-scales of the BPI are three-dimensional;2. (2) the three factors are Psychiatric Symptomatology, Social Symptomatology, and Depression;3. (3) this structure is invariant over the populations studied to date. Conclusions made about structure, however, are a function of the technique employed. Conclusions (1)–(3) were reached via the traditional factor/component analysis program of investigation. In the present study facet analysis and multidimensional scaling were used in a reanalysis of BPI data from nine different samples. The results indicated that the BPI is more satisfactorily portrayed as a two-dimensional radex (Guttman, Educational and Psychological Measurement, 17, 391–407, 1957). Cross-sample invariance was still obtained. The discovery of the radex structure of the BPI suggests links to other circular characterizations of Personality and Psychopathology variables, several of which were discussed.