An item response theory analysis of the narcissistic personality inventory.

This research uses item response theory methods to evaluate the Narcissistic Personality Inventory (NPI; Raskin & Terry, 1988). Analyses using the 2-parameter logistic model were conducted on the total score and the Corry, Merritt, Mrug, and Pamp (2008) and Ackerman et al. (2011) subscales for the NPI. In addition to offering precise information about the psychometric properties of the NPI item pool, these analyses generated insights that can be used to develop new measures of the personality constructs embedded within this frequently used inventory.