The classification of personality disorders: crouching categories, hidden dimensions.

Background.- The categorical model adopted in ICD-10 and DSM-IV-TR for the classification and diagnosis of PDs has been criticized for a number of reasons.
Aims.- To review the scientific basis of the categorical model and to examine alternate ways for classifying and diagnosing disorders of personality.
Method.- Literature review available up to August 2011.
Results.- The quality of the psychometric properties of the categorical model (i.e. interrater reliability, stability over time, discriminant validity, sensitivity and overall coverage) has generally been found poor. Various alternative models, including dimensional, hybrid dimensional-categorical and severity models, are currently being examined by the workgroups in charge of drafting proposals for ICD-11 and DSM-5.
Conclusion.- The categorical model for classifying personality pathology will be discarded in ICD-11 and DSM-5 in favour of a hybrid dimensional-categorical model and/or a model based on severity.