Preserving borderline personality disorder within dimensionalized personality disorder assessment: a clinical sequencing model

Borderline personality disorder (BPD) is a clinically significant and extensively studied personality disorder (PD), associated with substantial impairment, risk, treatment needs, and health-system burden. Contemporary debates about its classification now occur within diagnostic systems that already move beyond purely categorical models, including ICD-11 and the DSM-5 Alternative Model for Personality Disorders. The central question is therefore not simply whether dimensional assessment should be incorporated into PD diagnosis, but how general personality disorder diagnosis, named categorical patterns, dimensional characterization, and outcome/risk assessment should be clinically coordinated. This article examines BPD as a focal case for this broader categorical-dimensional problem. We review the clinical contributions and limitations of categorical and dimensional approaches, consider evidence supporting the reliability, validity, clinical utility, and treatment relevance of BPD, and propose a clinical sequencing model for PD assessment. The model is not intended as a new diagnostic architecture or diagnostic algorithm. Rather, it begins with establishing the presence of general personality disorder, then asks whether a named PD pattern is clinically meaningful, before proceeding to dimensional characterization and outcome/risk assessment. We argue that dimensional progress does not require the abandonment of named personality disorder diagnoses when they remain clinically and empirically meaningful. Within this framework, BPD can remain an organizing construct while categorical diagnosis is prevented from becoming the endpoint of clinical formulation.