Schizophrenia – what’s wrong
with this joke?
What the Specification Says:
Candidates will be expected to:
• develop knowledge and understanding of theories
and studies relevant to the content for each area of
psychology in this unit
• analyse and evaluate theories and studies
relevant to the content for each area of psychology
in this unit
• undertake practical research activities involving
collection, analysis and interpretation of qualitative
and quantitative data.
• Schizophrenia is not a multiple personality
• A psychotic disorder involving a break with
• Many different manifestations with a few
shared features
Schizophrenia diagnosis
• At least two of the following:
– Hallucinations (us. auditory or somatic)
– Delusions (oft. linked to hallucinations)
– Disorganised speech
– Disorganised or catatonic behaviour
– Negative symptoms
• Social & occupational dysfunction
• Duration of several months
Schizophrenia diagnosis
• Diagnostic subtypes
• Type 1 - Episodic, mainly positive symptoms
• Type 2 - Chronic, mainly negative symptoms
Schizophrenia prevalence
• 1% lifetime risk in general population
• Holds true for most geographical areas
although rates do vary
– Abnormally high in Southern Ireland, Croatia;
significantly lower rates in Italy, Spain (Torrey,
• Risk factors include low SES, minority
ethnicity, urban residence
Schizophrenia onset
Source: CIHI (2001)
Schizophrenia prognosis
• ‘Rule of the thirds’ (rule of thumb):
– 1/3 recover more or less completely
– 1/3 episodic impairment
– 1/3 chronic decline
• Confirmed in US & UK (Stevens, 1978)
• With treatment about 60% of patients manage a
relatively normal life
• Prognosis better in non-industrialised societies
• Most mental disorders are categorised into
• Diagnostic and Statistical Manual of Mental
Disorders (DSM) is produced in the US
• International Classification of Diseases (ICD)
produced in Europe
• Schizophrenia is major example of psychotic
Nature of Schizophrenia
• Characterised by a profound disruption of
cognition and emotion which affects a person’s
language, thought, perception, affect and even
sense of self.
• Media often links to violence. However only 8%
of diagnosed Schizophrenics in a year will commit
a serious act of violence.
This is less than the percentage of depressives or
people with personality disorders who will commit
an act of violence
Positive Symptoms
Experiences of Control
Disordered Thinking
Negative Symptoms
• Affective flattening
• Alogia
• Avolition
Can Scientists Agree on the same Diagnosis?
• DSM III introduced in 1980. Designed
specifically to provide more reliability
• Subsequent revisions but still questions over
• Recent studies found inter-rater reliability
correlations as low as 0.11 (Whaley 2001)
• Positive symptoms may be more suited for
diagnosis - Klosterkotter et al (1994)
• Argued that Schizophrenia is too broad a category
for it to be a useful diagnosis. Two patients could
have completely different symptoms
• Mojtabi and Nicholson (1995)
– 50 US psychiatrists asked to distinguish bizarre and
non-bizarre delusions. Inter-rater reliability
correlation of around 0.40
Can Scientists agree on what schizophrenia is?
• Bentall et al (1988) – comprehensive review of
symptoms (aetiology), prognosis (outcome)
and treatment concluded that Schizophrenia is
not a useful scientific category.
• Schneider (1959) ‘first rank’ symptoms –
designed to uniquely identify schizophrenia
• Ellason and Ross (1995) people with DID
(dissociative identity disorder) have more first
rank symptoms than schizophrenics!
• Little predictive validity – prognosis varies
• c. 20% recover to previous levels of functioning,
10% achieving lasting improvement, 30% some
improvement with relapses.
• Malmberg et al. (1998) – Prognosis is more to do
with Gender
• Harrison et al. (2001) – Prognosis is more to do
with psychosocial factors.
Rosenhan 1973
Cultural Differences
• Copeland et al (1971)
• Description of a patient to 134 US and 194
British psychiatrists
• 69% of the US psychiatrists diagnosed
• 2% of the UK psychiatrists diagnosed
a) Outline clinical characteristics of
schizophrenia. (6 marks)
b) Explain issues of reliabiility and validity
associated with the classification and
diagnosis of schizophrenia. (3+ 16 marks)

Schizophrenia - Psycho School