13.1.1

(2026 Exam) Classification & Diagnosis

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Classification and Diagnosis of Schizophrenia

Schizophrenia is a mental disorder. It is characterised by disruption in psychological functioning and loss of contact with reality.

Illustrative background for Schizophrenia in the populationIllustrative background for Schizophrenia in the population ?? "content

Schizophrenia in the population

  • Schizophrenia affects about 1% of the population.
  • Symptoms first show in mid to late adolescence.
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Psychological classification

  • There are currently two main classification systems for the diagnosis of mental disorders:
    • The International Classification of Diseases, Edition 10 (ICD-10), published by the World Health Organisation.
    • The Diagnostic and Statistical Manual (DSM-5), published by the American Psychiatric Association.
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Key features of classification systems

  • ICD-10 and DSM-5 classify schizophrenia slightly differently.
  • DSM-5 needs only one positive symptom (delusions, hallucinations) to be present for diagnosis.
  • ICD-10 needs two or more negative symptoms.
  • ICD-10 recognises sub-types of schizophrenia (paranoid schizophrenia, hebephrenic schizophrenia and catatonic schizophrenia).
    • These sub-types were omitted from the current edition of the DSM, even though they were present in previous editions.
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Types of schizophrenia

  • Paranoid schizophrenia is characterised by powerful delusions and hallucinations but relatively few other symptoms.
  • Hebephrenic schizophrenia involves mainly negative symptoms.
  • Catatonic schizophrenia involves disturbance to movement, leaving the sufferer immobile or overactive.

Jump to other topics

1Social Influence

2Memory

3Attachment

4(2026 Exams) Psychopathology

5(2027 Exams) Clinical Psychology & Mental Health

6Approaches in Psychology

7Biopsychology

8Research Methods

8.1Research Methods

8.2Scientific Processes

8.3Data Handling & Analysis

8.4Inferential Testing

9Issues & Debates in Psychology (A2 only)

10Option 1: Relationships (A2 only)

10.1Relationships: Sexual Relationships (A2 only)

10.2Relationships: Romantic Relationships (A2 only)

10.3(2026 Exams) Relationships: Virtual (A2 only)

10.4(2027 Exams) Relationships: Online (A2 only)

11Option 1: Gender (A2 only)

12Option 1: Cognition & Development (A2 only)

13Option 2: Schizophrenia (A2 only)

14Option 2: Eating Behaviour (A2 only)

15Option 2: Stress (A2 only)

16Option 3: Aggression (A2 only)

17Option 3: Forensic Psychology (A2 only)

18Option 3: Addiction (A2 only)

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