Assessment of personality organization in couple relationships: factorial structure of the inventory of personality organization and incremental validity over neuroticism.

Drawing on a sample of 372 French-Canadian couples, this study examined the factorial structure of a 20-item abbreviated version of the Inventory of Personality Organization (IPO) across a sample of couples and tested if identity diffusion, primitive defenses, and reality testing explain additional variance in couple distress when controlling for neuroticism. The IPO is based on Kernberg's conceptualization of personality organization (Kernberg, 1976 ). Gender differences were also studied through an examination of the value of both self-reported and partner-reported personality in the prediction of each partner's couple satisfaction. Results of confirmatory factor analyses indicated that the tripartite model of the short version of the IPO provided an acceptable fit and proved invariant when tested on couples. Actor-Partner Interdependence Model analyses (Kenny, Kashy, & Cook, 2006 ) showed that elevated neuroticism predicted higher endorsement of primitive defenses, which in turn predict couple dissatisfaction. There was also a direct, negative path from neuroticism to dyadic adjustment. Finally, self-reported neuroticism scores predicted high utilization of primitive defenses by the partner, and low partner-reported couple satisfaction. Furthermore, high self-reported utilization of primitive defenses predicted low couple satisfaction.