The Psychometric Properties and Sensitivity to Change of the Level of Personality Functioning Scale-Brief Form 2.0 in a Large Naturalistic Psychiatric Sample.

The DSM-5 Alternative Model for Personality Disorders (AMPD) identifies impairments in self and interpersonal functioning, Criterion A, as central to personality pathology. One measure that has been developed to measure Criterion A impairment is the Level of Personality Functioning Scale-Brief Form 2.0 (LPFS-BF 2.0), a brief, self-report questionnaire. The present study investigated the psychometric properties, factor structure, and change across brief treatment of the LPFS-BF 2.0 in a large, naturalistic psychiatric sample. Patients (N = 820) completed the LPFS-BF 2.0 alongside psychiatric measures at admission and discharge at a brief, intensive partial hospital program. The LPFS-BF 2.0 demonstrated good internal consistency and convergent validity. Confirmatory factor analysis generally supported a two-factor structure, with modifications improving fit. As hypothesized, LPFS-BF 2.0 total and subscores did not change significantly from pre-to post-treatment. Altogether, we present the largest psychometric evaluation of the LPFS-BF 2.0 in a transdiagnostic partial hospital sample serving patients with acute needs, with and without personality disorders. Our findings provide incremental support for the reliability, convergent validity, and clinical utility of the LPFS-BF 2.0 as a brief screening tool in transdiagnostic psychiatric settings.