The Level of Personality Functioning Scale-Brief Form 2.0: Update of a brief instrument for assessing level of personality functioning.

Section III of the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) introduced the alternative model of personality disorders that includes assessing levels of personality functioning. Here, we describe the development, preliminary psychometric evaluation and sensitivity to change of a revised brief self-report questionnaire, the Level of Personality Functioning Scale-Brief Form 2.0 (LPFS-BF 2.0). Patients (N = 201) referred to a specialized centre for the assessment and treatment of personality disorders completed the LPFS-BF 2.0, the Brief Symptom Inventory and the Severity Indices of Personality Problems Short Form and were administered the Structured Clinical Interview for DSM-IV Axis I and Axis II Disorders. Internal structure and aspects of construct validity were examined. A subsample of 39 patients also completed the questionnaires after 3 months of inpatient treatment. Confirmatory factor analyses demonstrated better fit for a two-factor solution (interpretable as self-functioning and interpersonal functioning) than for a unidimensional model, though acceptable model fit was evident only after two post hoc modifications. The LPFS-BF 2.0 demonstrated satisfactory internal consistency and promising construct validity. Sensitivity to change after 3 months of treatment was high. The LPFS-BF 2.0 constitutes a short, user-friendly instrument that provides a quick impression of the severity of personality pathology.