THE MODERN ASSESSMENT OF PERSONALITY-DISORDERS - PART 2 - RELIABILITYAND VALIDITY OF PERSONALITY-DISORDERS

Although both dimensional and categorical approaches to an assessment of personality disorders (PD) exist, only instruments for a categorica l approach to the assessment of PD have been developed. The reliabilit y of the diagnostic assessment of PD could be improved by using questi onnaires, checklists, and structured interviews. However, a comparison of structured interviews among themselves and with checklists or self -rating questionnaires showed only insufficient to satisfactory agreem ent, Therefore, there are no instruments for the assessment of DSM-III /DSM-IV and ICD-10 PD that could be clinically and scientifically inte rchanged. There is an increasing tendency to a dimensional approach to the assessment of PD. There are two approaches, a dimensional and a c ategorical one, to the assessment of personality disorders (PD). Chara cteristics of both approaches will be discussed before proceeding to t he assessment of PD. The categorical approach is identical to the desc ription of types given by the authors of classical psychiatry and refe rred to in part 1 [1]. In modern operationalised diagnostics the types are described by criteria (= behaviour and symptoms) with the number of criteria an individual must present in order to receive a diagnosis that is arbitrarily fixed. Thus, a 'cut-off point' decides whether an individual receives a diagnosis of PD or not. In the dimensional appr oach there is no such cut-off point.