Defining disordered personality functioning.

Current definitions of the PDs commonly combine descriptors of personality style and disordered personality functioning. This leads to artefactual comorbidity of formally separate disorders and compromising of diagnostic precision. We suggest that measurement of disordered functioning alone might provide a more efficient and precise first-level measure of PD. We review candidate constructs for the definition of disordered functioning and consider how constructs might be refined in subsequent research and lead to applied measures.