A hierarchy of items within Eysenck’s EPI

Based on the recent finding of a hierarchical scale for Neuroticism in the NEO-Five Factor Inventory, a further personality inventory: the Eysenck Personality Inventory was analysed using the Mokken Scaling Procedure for hierarchical scales. Items from two dimensions of the Eysenck Personality Inventory – Neuroticism and Extraversion – produced reliable hierarchical scales of 12 and five items, respectively, for all subjects but only a scale for Neuroticism for males and females separately. The Neuroticism items ran from items expressing mild to more extreme worry and a single hierarchical scale for Neuroticism, usable with males and females, is suggested. The utility of hierarchical scales in personality measurement is discussed in terms of furthering the theoretical understanding of personality traits and also their practical applications.