Personality Disorders: A Three-Dimensional Review
Introduction
The DSM-5 and ICD-10 classify personality disorders (PDs) as distinct, categorical entities.
This categorization has been challenged by studies suggesting PDs exist on a continuum, ranging from well-functioning to dysfunctional.
Limitations of the categorical system include high comorbidity and heterogeneity within PDs, questioning the validity of PDs as separate constructs.
These limitations hinder research and clinical practice.
The Alternative DSM-5 Model for PDs (AMPD) was proposed to address these issues but wasn't adopted into the official diagnostic codes, previous DSM-IV criteria were maintained for DSM-5.
The AMPD stipulates impairments in personality functioning (Criterion A) and pathological personality traits (Criterion B) as essential for PD diagnosis.
The AMPD has spurred research and interest in dimensional PD assessments, including the ICD-11 proposal and concepts of personality structure and organization.
Dimensional Approaches to Personality Disorders
Personality functioning, structure, and organization differ from categorical classifications by defining pathology dimensions based on disturbances in self and interpersonal relations, existing on a continuum from normal to severely disturbed functioning.
Personality Functioning
Conceptual Framework:
Operationalized by the Levels of Personality Functioning Scale (LPFS), synthesizing various measures of general personality psychopathology.
Four dimensions: identity, self-direction, empathy, and intimacy.
The first two reflect self-functioning, and the latter two reflect interpersonal functioning.
Five levels of impairment (0 to 4) are rendered to a single continuum.
Moderate or greater impairment (level 2 or higher) is essential for PD diagnosis according to the AMPD (Criterion A).
Criterion B involves pathological personality traits capturing disorder-specific characteristics.
The AMPD allows for the classification of six specific PDs (antisocial, avoidant, borderline, narcissistic, obsessive-compulsive, and schizotypal) characterized by personality functioning impairments.
Empirical Background:
Studies on the reliability and structure of personality functioning have been reviewed, including convergent validity with PD conceptualizations, personality traits, mental and physical dysfunction indicators, and interpersonal problems.
Personality functioning has been discussed against backgrounds such as the DSM classification, psychodynamic models, object relations, interpersonal theory, schema therapy, stress, neurobiology, and psychopathology taxonomy.
Instruments:
The LPFS serves as an expert rating instrument.
Self-report measures include the LPFS–Self Report, LPFS–Brief Report, DSM-5 Levels of Personality Functioning Questionnaire, Levels of Personality Functioning Questionnaire for Adolescents, and the Self and Interpersonal Functioning Scale.
Structured interviews: Clinical Assessment of the LPFS, Semi-Structured Interview for Personality Functioning DSM-5 (STiP-5.1), and Structured Clinical Interview for the DSM-5 Alternative Model for Personality Disorders–Module I (SCID-5-AMPD-I).
Evidence supports the validity and reliability of these measures, especially STiP-5.1 and SCID-5-AMPD-I.
Both interviews divide each LPFS domain into three subdomains, rated from 0 (
Introduction
The DSM-5 and ICD-10 use a categorical approach to classify personality disorders (PDs) as distinct.
This approach is controversial due to studies suggesting PDs exist on a continuum, from well-adjusted to severely dysfunctional.
The categorical system's limitations include high comorbidity (co-occurrence of multiple disorders) and heterogeneity (variability) within PDs, which questions the validity of PDs as separate constructs.
These issues complicate both research efforts and clinical application.
The Alternative DSM-5 Model for PDs (AMPD) was created to solve these problems but wasn't included in the official diagnostic codes; the DSM-5 retained the original DSM-IV criteria.
The AMPD requires impairments in personality functioning (Criterion A) and pathological personality traits (Criterion B) to diagnose a PD.
The AMPD has encouraged research and interest in dimensional PD assessments, including the ICD-11 proposal and concepts related to personality structure and organization.
Dimensional Approaches to Personality Disorders
Unlike categorical classifications, dimensional approaches define personality pathology based on disturbances in self and interpersonal functioning. These disturbances are viewed as dimensions on a continuum, ranging from normal to severely disturbed.
Personality Functioning
Conceptual Framework:- The Levels of Personality Functioning Scale (LPFS) is used to operationalize personality functioning, integrating various measures of general personality psychopathology.
It includes four dimensions: identity (sense of self), self-direction (goal orientation), empathy (understanding others' feelings), and intimacy (depth in relationships).
The first two reflect self-functioning, while the latter two reflect interpersonal functioning.
Impairment is rated across five levels (0 to 4), forming a single continuum.
As per the AMPD (Criterion A), a diagnosis of PD requires moderate or greater impairment (level 2 or higher).
Criterion B involves assessing pathological personality traits to capture disorder-specific characteristics.
The AMPD allows for the classification of six specific PDs (antisocial, avoidant, borderline, narcissistic, obsessive-compulsive, and schizotypal) based on impairments in personality functioning and pathological traits.
Empirical Background:- Research on the reliability and structure of personality functioning has been reviewed, including how it correlates with PD conceptualizations, personality traits, indicators of mental and physical dysfunction, and interpersonal problems.
Personality functioning has been examined in relation to the DSM classification, psychodynamic models, object relations theory, interpersonal theory, schema therapy, stress responses, neurobiology, and psychopathology taxonomy, providing a comprehensive understanding of its role in mental health.
Instruments:- The LPFS is designed for use by expert raters.
Self-report measures include the LPFS–Self Report, LPFS–Brief Report, DSM-5 Levels of Personality Functioning Questionnaire, Levels of Personality Functioning Questionnaire for Adolescents, and the Self and Interpersonal Functioning Scale; these provide individual perspectives on their functioning.
Structured interviews: Clinical Assessment of the LPFS, Semi-Structured Interview for Personality Functioning DSM-5 (STiP-5.1), and Structured Clinical Interview for the DSM-5 Alternative Model for Personality Disorders–Module I (SCID-5-AMPD-I) offer standardized assessments.
Evidence supports the validity and reliability of these measures, especially STiP-5.1 and SCID-5-AMPD-I, making them useful for both research and clinical settings.
Both the STiP-5.1 and SCID-5-AMPD-I interviews divide each LPFS domain into three subdomains, which are then rated from 0