Since the publication of the Alternative Model on Personality Disders in Section III DSM-5, literature has widely focused on providing validity evidence for the 25 facets defined in Criterion B. More recently, scientific attention has shifted towards Criterion A, with a considerable set of mixed results both supporting and disagreeing the operational definition of the model.
The present study aims to provide additional evidence on the structural and relational differentiation of self and interpersonal dimensions of personality functioning using a quick screener, the Level of Personality Functioning Scale – Brief Form 2.0 (LPFS-BF 2.0), in a community and clinical mixed sample.
1074 participants (717 community adults and 357 patients) completed the LPFS-BF 2.0, the Personality Inventory for DSM-5 Short Form and the Questionnaire for the World Health Organization Disability Assessment. The internal structure of LPFS 2.0 was assessed through a series of Confirmatory Factor Analyses and bifactor modeling was applied to assess the dimensionality. Exploratory Structural Equation Modelling was used to explore the joint structure of functioning and maladaptive traits. Multiple linear regressions, controlling for age and sex, were employed to evaluate the predictive validity of LPFS scales in explaining functional impairment.
Our results clearly support a two-factor structure of criterion A (self and interpersonal functioning) when measured with LPFS-BF 2.0. Results also displayed clear differences between the personality functioning factors, with the self-functioning factor more closely linked to facets of the negative affect domains and the interpersonal-functioning factor linked to several antagonistic personality traits. Moreover, our results suggested a relevant role of self-functioning in the explanation of the functional impairment along and beyond personality facets.
These results lead to consider the LPFS-BF 2.0 a useful tool for clinical routine monitoring self and interpersonal personality functioning.