BPA Jan-11 Problems of schizophrenia Classification & Diagnosis

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?

DSM- IV The Diagnostic and Statistical Manual of Mental Disorder (Edition 4), was last published in The DSM is produced by the American Psychiatric Association. It is the most widely used diagnostic tool in psychiatric institutions around the world.

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 10 th edition Diagnosing a mental disorder is almost always done using the DSM-IV and / or the ICD-10. 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? 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? 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. I really hope I agree with that other bloke!

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. Rosenhan et al (1972). 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!

What psychiatrists don’t understand 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? Meehl (1977) Suggested that mental health professionals should be able to count on the diagnostic tools if they: 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. 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.

Cultural Relativism 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.

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

How to revise this topic: DSM IV – written by APA – last published in 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) – 1 st rank symptoms (too stringent). Other things can produce schizophrenic-like symptoms.