Dr. Cox Published in Personality Disorders: Theory, Research, and Treatment!

Ruiz, M., Hopwood, C., Edens, J.F., Morey, L.C., & Cox, J. (2018). Initial development of pathological personality traits domain measures using the Personality Assessment Inventory (PAI). Personality Disorders: Theory, Research, and Treatment.

This study set out to create measures of the five personality disorder trait domains outlined in Section III of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (American Psychiatric Association, 2013) from the Personality Assessment Inventory items (Morey, 2007). Rasch rating scale model analyses and classical test theory analyses were applied to existing data sets (N = 3,877; community, clinical, offender, college) to identify relevant items. Five scales were created that had acceptable unidimensionality and generally conformed to Rasch model expectations. The ability of the items to cover the underlying construct and their differential item function by sex were acceptable, though a few of the proposed scales had weaknesses in these areas. Internal consistency was acceptable for all scales and the factor structure was generally consistent with expectations, but some scales had concerning cross-loadings. Preliminary analyses demonstrated validity of the scales in relation to history of mental health treatment/current symptoms, substance abuse, and, for one scale, violent rearrests. There were small-to-moderate associations with noncorresponding traits, suggesting a degree of saturation with general personality impairment. The relevance of the proposed scales for the assessment of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition personality disorder is discussed.