Psych · General adult psychiatry — personality disorders
Cluster A and Cluster C personality disorders
Also known as Paranoid personality disorder · Schizoid personality disorder · Schizotypal personality disorder · Avoidant personality disorder · Dependent personality disorder · Obsessive-compulsive personality disorder · OCPD · Anankastic personality disorder · Cluster A · Cluster C
Exam-exhaustive fellowship reference on Cluster A (paranoid, schizoid, schizotypal) and Cluster C (avoidant, dependent, OCPD) personality disorders — DSM-5-TR criteria, ICD-11 severity and trait domains, epidemiology, mechanisms, differentials (ASD, social anxiety, OCD, schizophrenia spectrum), assessment, psychotherapy and limited pharmacotherapy, prognosis. FRANZCP-primary, globally tagged.
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10 MCQs with explanations
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Red flags
Meet the patient
A 38-year-old surgeon is referred by his own department head. He stays three hours after every list rewriting his registrars' notes. He cannot delegate a discharge summary because "nobody else meets the standard." His wife has stopped attending his dinners. He presents, politely, to ask why everyone around him has such low standards — and he genuinely wants an answer.[16][17]
The examiner's question is not "does he have OCD?" It is: "Why is this not OCD, and what treatment do you offer a man who thinks he is right?" That answer is this topic.[14][15]
You have read the opening of this topic. The complete unit — every section and its primary-source references — is part of the Psychiatry Fellowship fellowship atlas.
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- [2]Lenzenweger MF, Lane MC, Loranger AW, Kessler RC DSM-IV personality disorders in the National Comorbidity Survey Replication Biol Psychiatry, 2007.PMID 17217923
- [3]Grant BF, Hasin DS, Stinson FS, Dawson DA, et al. Prevalence, correlates, and disability of personality disorders in the United States: results from the national epidemiologic survey on alcohol and related conditions J Clin Psychiatry, 2004.PMID 15291684
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- [5]Bamelis LL, Evers SM, Spinhoven P, Arntz A Results of a multicenter randomized controlled trial of the clinical effectiveness of schema therapy for personality disorders Am J Psychiatry, 2014.PMID 24322378
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- [8]Rosell DR, Futterman SE, McMaster A, Siever LJ Schizotypal personality disorder: a current review Curr Psychiatry Rep, 2014.PMID 24828284
- [9]Cheli S, Wisepape CN, Witten CDY, Floridi M, et al. Psychosocial and pharmacological interventions for cluster a personality disorders: A systematic review and two exploratory meta-analyses Personal Disord, 2025.PMID 40111791
- [10]Jakobsen KD, Skyum E, Hashemi N, Schjerning O, et al. Antipsychotic treatment of schizotypy and schizotypal personality disorder: a systematic review J Psychopharmacol, 2017.PMID 28347257
- [11]Gundersen KB, Arnfred B, Albert N, Rasmussen AR, et al. Treatment of schizotypal disorder: A systematic review and GRADE evaluation of the certainty of evidence Schizophr Res, 2026.PMID 41421074
- [12]Lampe L, Malhi GS Avoidant personality disorder: current insights Psychol Res Behav Manag, 2018.PMID 29563846
- [13]Frandsen FW, Simonsen S, Poulsen S, Sørensen P, et al. Social anxiety disorder and avoidant personality disorder from an interpersonal perspective Psychol Psychother, 2020.PMID 30656823
- [14]Pozza A, Starcevic V, Ferretti F, Pedani C, et al. Obsessive-Compulsive Personality Disorder Co-occurring in Individuals with Obsessive-Compulsive Disorder: A Systematic Review and Meta-analysis Harv Rev Psychiatry, 2021.PMID 33666394
- [15]Mancebo MC, Eisen JL, Grant JE, Rasmussen SA Obsessive compulsive personality disorder and obsessive compulsive disorder: clinical characteristics, diagnostic difficulties, and treatment Ann Clin Psychiatry, 2005.PMID 16402751
- [16]Pinto A, Teller J, Wheaton MG Obsessive-Compulsive Personality Disorder: A Review of Symptomatology, Impact on Functioning, and Treatment Focus (Am Psychiatr Publ), 2022.PMID 37200888
- [17]Diedrich A, Voderholzer U Obsessive-compulsive personality disorder: a current review Curr Psychiatry Rep, 2015.PMID 25617042
- [18]Lugnegård T, Hallerbäck MU, Gillberg C Personality disorders and autism spectrum disorders: what are the connections? Compr Psychiatry, 2012.PMID 21821235
- [19]Gjerde LC, Czajkowski N, Røysamb E, Orstavik RE, et al. The heritability of avoidant and dependent personality disorder assessed by personal interview and questionnaire Acta Psychiatr Scand, 2012.PMID 22486635
- [20]Kim YR, Tyrer P, Mulder R, King JD, et al. ICD-11 classification of personality disorder: there is no other way forward Br J Psychiatry, 2026.PMID 41906979