A principal components analysis of Rorschach aggression and hostility variables.

We examined the structure of 9 Rorschach variables related to hostility and aggression (Aggressive Movement, Morbid, Primary Process Aggression, Secondary Process Aggression, Aggressive Content, Aggressive Past, Strong Hostility, Lesser Hostility) in a sample of medical students (N= 225) from the Johns Hopkins Precursors Study (The Johns Hopkins University, 1999). Principal components analysis revealed 2 dimensions accounting for 58% of the total variance. These dimensions extended previous findings for a 2-component model of Rorschach aggressive imagery that had been identified using just 5 or 6 marker variables (Baity & Hilsenroth, 1999; Liebman, Porcerelli, & Abell, 2005). In light of this evidence, we draw an empirical link between the historical research literature and current studies of Rorschach aggression and hostility that helps organize their findings. We also offer suggestions for condensing the array of aggression-related measures to simplify Rorschach aggression scoring.