Personality disorders are examined as part of general adult psychiatry in Paper B. The ICD-11 moved from the categorical approach of ICD-10 (10 distinct types) to a dimensional model, which is a recurring topic in recent examinations. Borderline personality disorder receives the most attention because of its clinical importance and specific evidence-based treatments. Defence mechanisms are a particular favourite in EMI-style questions.
ICD-11 Dimensional Model
ICD-11 replaced the 10 categorical types with a single personality disorder diagnosis graded by severity (mild, moderate, severe). Trait domain qualifiers: negative affectivity, detachment, dissociality, disinhibition, anankastia. The borderline pattern specifier was retained because of specific treatment implications (DBT).
Borderline Personality Disorder
Defence mechanisms (exam-favourite): Splitting (all-good/all-bad), acting out (self-harm as the classic example), projective identification, idealisation and devaluation. ICD-11 specifically identifies acting out as a key feature. Splitting is the most commonly tested defence in BPD.
NICE management: DBT specifically for women with recurrent self-harm. MBT and TFP are also evidence-based. Medication should not be prescribed specifically for BPD core symptoms — treat comorbid conditions only.
Antisocial Personality Disorder
Pervasive disregard for rights of others, present from age 15 (diagnosis from 18). Forensic associations (recall-confirmed): ASPD + LD + substance abuse = most common with sexual offending and theft. Group-based CBT (thinking skills programmes) rather than individual therapy.
Other Key Distinctions
- Schizotypal vs schizoid: Schizotypal = anxiety + desire relationships but socially awkward. Schizoid = aloof, indifferent, prefers solitude.
- Avoidant vs schizoid: Avoidant WANTS relationships but fears rejection. Schizoid has no desire.
- OCPD vs OCD: OCPD = personality pattern, believes their way is right. OCD = recognises behaviours as excessive.
High-Yield Recall Patterns
- Most common defence in BPD (ICD-11): Splitting AND acting out
- Persistent anxiety + social anxiety: Schizotypal PD (NOT schizoid)
- Sexual reoffending strongest predictor: Sexual deviancy + antisocial PD
- BPD + recurrent self-harm: DBT (NICE-recommended)
- ASPD treatment: Group-based CBT / thinking skills programmes
- ICD-11 change: Dimensional model. Borderline specifier retained for DBT implications.
PsychStar’s Paper B question bank covers personality disorders with questions calibrated to real exam difficulty. Start with 5 free questions at psychstar.io/try.