A01: Diagnosis & Classification of Sz

• Diagnosis & Classification of Schizophrenia:

  • Prevalence
  • Diagnosis vs Classification
  • Classification: DSM-5 and ICD-10 differ
  • Symptoms/diagnosis: + & -
• Who is most likely to suffer from Sz/prevalence?

  A serious mental disorder affecting about 1% of the population suffer from SZ.

  • More Males suffer from SZ
  • More likely to affect city-dwellers
  • More likely to affect lower socio-economic groups (working people)
• Diagnosis vs Classification?

  Diagnosis and classification are interlinked.

  To diagnose a specific disorder, we need to be able to distinguish one disorder from another.

  • Classification - identity symptoms that go together = a disorder
  • Diagnosis - identify symptoms and use classification system to identify the disorder (e.g. depression, OCD, schizophrenia etc).
• How is SZ classified?

  • DSM-5 (APA's Diagnostic & Statistical Manual of Mental Disorders)
  • ICD-10/11 (WHO's The International Classification of Diseases)

  DSM-5 and ICD-10 differ
• There are 2 main classification systems in use:

  DSM-5: One positive symptom must be present

  • Needs one of the so called positive sumptoms to be present for diagnosis
  • Subtypes removed
  • Positive symptoms = delusions, hallucinations or speech disorganisation

  ICD-10: (V11 published but not used for diagnosis until 2022): 2 or more negative symptoms are sufficient for diagnosis

  • 2 or more negative symptoms adequate for diagnosis
  • 5 subtypes recognised
  • Negative symptoms = Avolition & speech poverty
• Symptoms of schizophrenia:

  • Positive
  • Negative
• Hallucinations

  • Unusual sensory experiences that have no basis in reality or distorted perceptions of real things/distortions of stimuli that are genuinely there - unreal perceptions of the env
  • Experienced in relation to any sense
  • For example, hearing voices or seeing people who are not there

  4 Types:

  • Tactile Hallucinations (related to touch e.g bugs crawling under skin)
  • Visual Hallucinations (related to vision e.g seeing lights, faces, objects)
  • Auditory Hallucinations (related to hearing e.g. hearing voices)
  • Olfactory Hallucinations (related to smell e.g smell things)
• Delusions

  • + symptom
  • Irrational beliefs that have no basis in reality and can take a range of forms - make a person with schizophrenia behave in ways that make sense to them but are bizarre to others.
  • Belief which seems real to the person but is not.
  • For example, beliefs about being a very important person or the victim of a conspiracy.

  Types:

  • Delusions of Paranoia (aka delusions of persecution)
  • Delusions of Control
  • Delusions of Grandeur
• Disordered Thinking/ speech disorganisation

  • + symptom
  • Concentration problems means sufferers struggle to maintain their train of though
  • Jumbled sentences
  • Side tracked:
  • Tangents
  • Tangential Speech
  • Incoherent speech
  • Racing thoughts
• Negative Symptoms

  These symptoms involve the 'loss' of usual abilities and experiences

  • Speech poverty
  • Avolition
• Speech Poverty

  • Characterised by changes in pattern of speech: Reduction in amount & quality of speech. May include delay in verbal responses during conversion.
  • DSM emphasises speech disorganisation & incoherence as a positive symptom.
  • Characteristics:
  • ALOGIA: where speech seems 'blocked'
  • ECHOLALIA: meaningless repetition of words
  • NEOLOGISMS: new words
  • WORD SALADS: jumble of words
  • Communication suffer from AFFECTIVE FLATTENING: where there reduction in range & intensity of emotions/emotional expression (Blank face, no expression, monotone, lacks body language & no eye contact)
• Avolition


  • Sometimes known as apathy
  • Lack of purposeful willed behaviour
  • Severe loss of motivation to carry out everyday tasks
  • Results in lowered activity & unwillingness to carry out goal-directed behaviours.

  Characteristics:

  • Lack of self care (e.g. poor personal grooming)
  • Lack of energy (e.g tiredness)
  • Lack of motivation/goal directed behaviour (often to carry out everyday tasks e.g. hobbies, personal care, work)
• Catatonic

  Need to repeat behaviours
• Positive Symptoms

  These symptoms are 'additional' experiences beyond those of ordinary existence.

  • Hallucinations
  • Delusions
  • Speech Disorganisation