Text adapted from: "The adult patient with a personality disorder," in Psychiatry in primary care by Michael Rosenbluth, Matthew Boyle & Lucille Schiffman (CAMH, 2019).
Screening for Personality Disorders
While primary care doctors may use screening tools for Borderline Personality Disorder (BPD), such as the McLean Screening Instrument for BPD (MSI-BPD), the Personality Diagnostic Questionnaire 4th edition—BPD Scale, and the Structured Clinical Interview for DSM-IV Axis II Personality Disorders -Patient Questionnaire—BPD Scale (SCID-II-PQ BPD) to help diagnose BPD and personality disorders), a single, definitive personality disorder test does not exist. Instead, clinicians diagnose BPD and personality disorders through a thorough assessment that emphasizes longitudinal difficulties, and not simply the cross sectional presentation.
Types of Personality Disorders
Currently, there are 10 personality disorders recognized in psychiatry. Borderline personality disorder and antisocial personality disorder are the most frequently diagnosed personality disorders (the others are listed below). The 10 personality disorders are grouped into three clusters according to shared characteristics. Each personality disorder has its own signs and symptoms, but there are similarities within each of the three clusters:
- Cluster A: paranoid, schizoid and schizotypal personality disorders. These are characterized by feeling paranoid, distrustful and suspicious.
- Cluster B: impulsive personality disorders, such as borderline, narcissistic, histrionic and antisocial personality disorders. These are characterized by having difficulty controlling emotions, fears, desires and anger.
- Cluster C: anxious personality disorders, such as obsessive-compulsive, dependent and avoidant personality disorders. These are characterized by experiencing compulsions and anxiety.
People with personality disorders are at increased risk for self-harming behaviours and suicide. They may also have more difficulty getting along with others than do people without personality disorders.