Problems of schizophrenia
Classification &
Diagnosis
BPA Jan-11
Schizophrenia: issues surrounding diagnosis
There are several issues surrounding the
diagnosis of Schizophrenia that need to be
assessed.
 These include addressing issues
surrounding the reliability and validity of
diagnosis.
 So first of all, how do we know what to look
for when diagnosing S?
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DSM- IV
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The Diagnostic and
Statistical Manual of Mental
Disorder (Edition 4), was last
published in 1994.
The DSM is produced by the
American Psychiatric
Association.
It is the most widely used
diagnostic tool in psychiatric
institutions around the
world.
ICD-10
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There is also the
International Statistical
Classification of Diseases
(known as ICD).
It is produced by the
World Health Organisation
(WHO) and is currently in
it’s 10th edition
Diagnosing a mental
disorder is almost always
done using the DSM-IV
and / or the ICD-10.
Reliability and validity of DSM-IV and ICD-10
The main issues surrounding the diagnosis of S
centre on the reliability & validity of the diagnosis
 Validity refers to how accurate and correct the
diagnosis is - ie. a diagnosis is valid if a
schizophrenic is actually diagnosed with S and not
another illness
 Reliability refers to the consistency and stability of
the diagnosis - ie. a person with S should
continually be given the diagnosis of schizophrenia
and not another illness no matter which doctor they
go and see

Inter-rater reliability – do psychiatrists agree?
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Beck et al (1961)
looked at the inter-rater
reliability between 2
psychiatrists when
considering the cases
of 154 patients.
The reliability was only
54% - meaning they
only agreed on a
diagnoses for 54% of
the 154 patients!
I wonder what
the other bloke
thinks?
Inter-rater reliability – do psychiatrists agree?
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I really hope I
agree with that
other bloke!
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A true diagnosis cannot be
made until a patient is
clinically interviewed.
Psychiatrists are relying on
retrospective data, given by
a person whose ability to
recall much relevant
information is
unpredictable.
Some patients may be
exaggerating the truth – or
just totally lying.
Reliability of DSM and ICD
It was originally hoped that the use of diagnostic
tools could provide a standardised method of
recognising mental disorders.
 However clear the diagnostic tool, the behaviour
of an individual is always open to some
interpretation. The process is subjective.
 The most famous study testing the subjectivity,
reliability and validity of diagnostic tools was
Rosenhan et al (1972).

On Being Sane in Insane Places
Rosenhan recruited 8 people (he worked with
them or knew him in some capacity).
 Each of the 8 people went to a psychiatric
hospital and reported only 1 symptom. That a
voice said only single words, like “thud”, “empty”
or “hollow”.
 When admitted, they began to act “normally”. All
were diagnosed with suffering from
schizophrenia (apart from 1).
 The individuals stayed in the institutions for
between 7 to 52 days.

On being sane… follow up
Rosenhan told the institutions about his results,
and warned the hospital that they could expect
other individuals to try & get themselves
admitted.
 41 patients were suspected of being fakes, and
19 of these individuals had been diagnosed by 2
members of staff.
 In fact, Rosenhan sent no-one at all!
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What psychiatrists don’t understand
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It is tempting to label a person as a
sufferer of schizophrenia, without
really knowing the extent to which
they are suffering.
The beliefs and biases of some might
mean the unnecessary labelling of
millions of people as sufferers of a
mental disorder.
Sometimes a disorder must reach a
particular level of severity before it
can be recognised with confidence as
a mental health issue.
Validity of diagnosis
Does the system of classification and diagnosis
reflect the true nature of the problems the
patient is suffering; the prognosis (the course
that the disorder is expected to take); and how
great a positive effect the proposed treatment
will actually have?
 Many individuals do not neatly fit into categories
that have been created. Instead of
acknowledging this, clinicians tend to diagnose 2
separate disorders.

How can we improve Validity of diagnosis?
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Meehl (1977) Suggested that mental health
professionals should be able to count on the
diagnostic tools if they:
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Paid close attention to medical records
Were serious about the process of diagnosis
Took account of the very thorough descriptions
presented by the major classificatory systems
Considered all the evidence presented to them.
But.. The reality.
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There is limited time and resources available of many
professionals working in the National Health Service.
Diagnoses can be made by professionals that are rushed,
and preoccupied with only admitting the most serious
cases in order to safeguard the resources of the
institution they are working for.
Labelling
The beliefs and biases of some
might mean the unnecessary
labelling of millions of people as
sufferers of a mental disorder.
 Someone diagnosed with a
mental disorder has to disclose
that information in situations
such as job interviews, or they
could face formal action.
 Unlike influenza, the label of
‘schizophrenic’ stays with a
person.
 Schizophrenics risk carrying the
stigma of their condition for the
rest of their lives.
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Cultural Relativism
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Davison & Neale (1994) explain
that in Asian cultures, a person
experiencing emotional turmoil is
praised & rewarded if they show no
expression of their emotions.
In certain Arabic cultures however,
the outpouring of public emotion is
understood and often encouraged.
Without this knowledge, an
individual displaying overt
emotional behaviour may be
regarded as abnormal, when in
fact it is not.
Schneider (1959)
Proposed a different approach to the diagnosis of
schizophrenia.
 He argued that the nature of the symptom that
would determine whether a person was
schizophrenic.
 He arrived at a number of “first rank symptoms”,
these included thought insertion and thought
broadcast, hearing voices and delusional
perceptions.
 This approach as been criticised as too stringent.
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A final thought…
A person cannot be diagnosed with the condition
if an existing mood disorder has been diagnosed
in the past or if the person is suffering from this
at present.
 It could also be the case that such symptoms are
brought about as a result of another medical
condition or the abuse of illegal drugs or other
medications.
 Organic problems such as brain tumours can
also produce schizophrenic-like symptoms
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How to revise this topic:
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DSM IV – written by APA – last published in 1994.
ICD – 10 – written by WHO.
Reliability – Beck (1961) – 54% agreement
Rosenhan study – subjectivity
Issues with severity – unnecessary labelling.
Validity – p’s don’t fit into categories
Labelling/Stigma
Cultural relativism – Davison & Neale (1994)
Schneider (1959) – 1st rank symptoms (too
stringent).
Other things can produce schizophrenic-like
symptoms.