Schizophrenia and diagnosis by Angeline David

SCHIZOPHRENIA PSYA4

WHAT DO YOU NEED TO KNOW?In relation to their chosendisorder:schizophrenia

Information to know

Clinical characteristics of Sz

Issues surrounding the classification and diagnosis of including reliability and validity

Biological explanations of Sz, for example, genetics,biochemistry

Psychological explanations of Sz; behavioural, cognitive, psychodynamic and socio-cultural

Biological therapies for their chosen disorder, including their evaluationin terms of appropriateness and effectiveness

Psychological therapies for Sz, for example, behavioural, psychodynamic and cognitive-behavioural, including their evaluation in terms of appropriateness and effectiveness

EXAM QUESTIONSa) Outline clinical characteristics of

schizophrenia. (4 marks)b) Explain issues of reliability and validity

associated with the classification and diagnosis of schizophrenia. (4+ 16 marks)

CLINICAL CHARACTERISTICS

Schizophrenia has been variously described as a disintegration of the personality

A main feature is a split between thinking and emotion.

It involves a range of psychotic symptoms (where there is a break from reality)

Generally, schizophrenic patients lack insight into their condition, i.e. they do not realise that they are ill.

They must follow the pattern of symptoms (see next slide)

POSITIVE SYMPTOMSPositive symptoms are an excess or distortion of normal functions which represent a change in behaviour or thoughts, to include:

DELUSIONS An unshakable belief in something that is

very unlikely, bizarre or obviously untrue. One of the delusions experienced in schizophrenia is paranoid delusions, where an individual believes that something, or someone, is deliberately trying to mislead, manipulate, hurt or, in some cases, even kill them.

Another common delusion is the delusion of grandeur, which is where an individual believes that they have some imaginary power or authority, such as thinking that they are on a mission from God or that

they are a secret agent.

HALLUCINATIONSAuditary/Visual- usually take the form of hearing voices that are not there. These voices are normally critical and unfriendly. Additionally, some people with schizophrenia may also see, smell, taste and feel things that are not there.

CATATONIC OR DISORGANISED BEHAVIOURwhere an individual behaves in ways that seem inappropriate or strange to the norms of society.

DISORGANISED SPEECHoften known as a ‘word salad’, where an individual speaks in ways that are completely incomprehensible. For instance, sentences might not make sense, or topic of conversation changes with little or no connection between sentences.

NEGATIVE SYMPTOMSare a diminution or loss of normal functionsto include: A lack, or 'flattening', of emotions, where a

person’s voice becomes dull and monotonous and their face takes on a constant blank appearance.

An inability to enjoy things that they used to enjoy.

Apathy, where they have a lack of motivation to follow through any plans and neglect household chores, such as washing the dishes or cleaning their clothes.

Social withdrawal, where they find it hard or become reluctant to speak to people.

SCHIZOPHRENIAISSUES OF CLASSIFICATION AND

DIAGNOSIS

EXAM QUESTION Explain issues of reliability and validity associated with the classification and diagnosis of schizophrenia. (8+ 16 marks)

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.

RELIABILITY OF CLASSIFICATION SYSTEMS Reliability refers to the consistency of a

measuring instrument, such as a questionnaire or scale, to assess for example, the severity of the schizophrenic symptoms.

Reliability of such questionnaires or scales can be measured in terms of whether 2 independent assessors give similar diagnosis (inter-rater reliability) or whether tests used to deliver these diagnoses are consistent over time (test-retest reliability)

CLASSIFICATION SYSTEMS

The two most widely used classifications systems for diagnosis of schizophrenia are:

DSM- IV 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 throughout America and some parts of Europe.

ICD - 10 International Statistical

Classification of Diseases (known as ICD)- produced in Europe by the World Health Organisation (WHO) and is currently in it’s 10th edition.

Used in the UK and many other European countries

DIFFERENCES BETWEEN DSM IV AND ICD 10: RELIABILITY

DSM IV versus ICD 10 all people diagnosed as suffering from

schizophrenia must have one or more of the clinical characteristics outlined above present for at least 6 months

ICD requires the signs to be apparent for one month.

What are the implications?

AO2 The ICD classification system appears to

offer some advantage over the DSM classification:

1. Firstly, with the symptoms only needing to be present for one month as opposed to six with the DSM, sufferers do not have so much time in which they may be at risk to themselves and others.

2. They also only have to live without help for one month before receiving diagnosis and therefore appropriate treatment.

COMPARISON OF CLASSIFICATION SYSTEMSDSM – multi-axial various factors

considered (bio, psychological, social)- takes account the individual and the situation rather than merely the symptoms as it assesses the sufferer’s social functioning such as poverty and physiological state of health-therefore- more informed decision,p303

ICD-

emphasis on first rank symptoms- ignores the social functioning/context of individual

DIFFS IN SUBTYPES ICD and the DSM do not entirely agree

on the number of subtypes of schizophrenia, with the ICD suggest seven different subtypes and the DSM five.

(AO2)The reliability here is questioned as a sufferer could be diagnosed as one type of schizophrenic according to the DSM and a different type according to the ICD.

Implications: incorrect treatment

WEAKNESS OF DSM Culturally- biased - created by Americans for Americans. Problem- as behaviour in one culture may not be regarded as a symptom of schizophrenia but according to the DSM it is. For instance, hearing voices in some cultures is considered to be a message and is regarded as an honour- not a symptom of a mental disorder. Implication: Incorrect diagnosis- incorrect treatment (drugs- side effects)

Reliability of diagnosis in schizophrenia is further challenged by the finding that there is massive variation between countries.

ICD- MORE UNIVERSAL less culturally biased - can be applied

to more diverse cultures as the World Health Organisation (creators of the ICD) are made up of representatives from 193 countries and therefore various cultures are represented.

INCONSISTENCY BETWEEN DIFFERENT EARLY CLASSIFICATION SYSTEMS. Prior to 1970’s – sig. diff. in prevalence rates of Sz in diff

countries. In America- DSM –too vague/contained broad diagnostic

criteria. Hampered research into causes and treatments. In US patients diagnosed with Sz rose from 20% in 1930’s

to 80% in 1950’s. In London, diagnosis rate remained constant throughout same period (Cooper et al 1972)

Copeland (1971) gave 124 US and 194 British psychiatrists a description of a patient.

- 69% of the US psychiatrists diagnosed schizophrenia- only 2% of British psychiatrists diagnosed schizophrenia

To eliminate diagnostic diffs, attempts were made to bring the major systems (ICD-10 and DSM-TR-IV) into line with one another –became similar- not identical

Despite claims for increased reliability in DSM-III and later versions, 30 years later there is still little evidence that DSM is routinely used with high reliability by mental health clinicians.

The problems with the medical classification were highlighted in the most famous investigation on hospital practices. “On Being Sane in Insane Places”, Rosenhan (1973): 

An all-time classic study in psychology that breaks some of the unwritten rules in that the real participants are the psychiatric establishment! 

Rosenhan (1973) aimed to test the hypothesis that psychiatrists cannot reliably tell the difference between people who are sane and those who are insane

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! A good film to watch: One Flew Over

the Cuckoo’s Nest (is Jack Nicholson’s character mentally ill? Is he mad, bad or sad? You decide!

ROSENHAN 1973http://www.youtube.com/watch?v=jXp-ANr8jAQ&feature=related

ROSENHAN 1973 This study highlighted the unreliability

of diagnosis. However, this study was conducted over 30 years ago. Since then manuals have been improved and diagnostic practise is very different. For example, categories and definitions are more detailed and operationalised and psychiatrists now use standardised interview schedules when assessing patients. Also the ICD and DSM have been bought in line with one another so they are now very similar.

IMPROVING RELIABILITYKurt Schneider (1959)- tried to make the diagnosis of Sz more reliable: He identified a group of symptoms

characteristic of S but rarely found in other mental disorders.

These ‘first-rank’ symptoms-useful in helping clinicians determine the diagnosis of S- formed the basis of the current ICD-10 classification.

THE USE OF OTHER DIAGNOSTIC TOOLS Along with the ICD and DSM clinicians use

other diagnostic tools to help diagnose schizophrenia (e.g. St. Louis Criteria, Schneider Criteria, Research Diagnostic Criteria). The fact that other criteria have been developed makes research comparisons difficult. It also highlights the difficultly clinicians have when deciding what exactly they mean by the diagnosis of schizophrenia. If the categories are poorly defined and arbitrary, consistent diagnosis (reliable diagnosis) is likely to be low.

(see Janet Frame p309; Rosenhan -1973)

INTER-RATER RELIABILITY The inter-rater reliability of

two psychiatrists diagnosing Schizophrenia is exceptionally low, e.g. less then 50%-suggests that psychiatrists do not know what they are doing. Thus people who do not have Schizophrenia may be included in research -may result in invalid conclusions about the cause of the ‘illness’ and/or treatment.

I wonder what the other bloke thinks?

INTER-RATER RELIABILITY Beck et al (1961) Found that agreement

on diagnosis for 153 patients (where each was assessed by two psychiatrists from a group of four) was only 54%. This was often due to vague criteria for diagnosis and inconsistencies in techniques to gather data. – Inter rater reliability.

Whaley (2001) found inter-rater reliability correlations in the diagnosis of schizophrenia as low as 0.11

Incorrect diagnosis -the result of problems with defining Schizophrenia, e.g. if you cannot classify Schizophrenia how can you diagnose it?

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 may be exaggerating the truth – or blatantly lying!

I really hope I agree with that other bloke!

THE NHS IS A WONDERFUL THING!

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.

USE OF SUB-TYPES Crow (1985) believes that Sz is too broad a term because at least two very different conditions exist. Type I syndrome- acute disorder characterised by positive

symptoms ( exaggerations of normal beh.) Type II syndrome- chronic disorder- negative symptoms

such as flattening of affect, apathy and poverty of speech. Further evidence for this view comes from research that

shows that Type 1 and Type 2 Schizophrenics do respond very differently to psychological and biological treatments, e.g. Typical and Atypical Phenothiazines have more success with relieving positive symptoms as does CBT.

Problems with above division- people do not fit neatly into one or other category.

Blurred distinction between some subtypes- some people diagnosed in one category later develop symptoms from another- weakens reliability

Moreover, Schizophrenia has many different categories and symptoms, e.g. Paranoid, Catatonic and Hebephrenic. Some of these subtypes have very different qualities; especially Catatonic Schizophrenia where the person can lay motionless in rigid poses for days.

VALIDITY Validity refers to the extent that a

diagnosis represents something that is real and distinct from other disorders and the extent that a classification system such as ICD or DSM measure what it claims to measure.

Reliability and Validity are linked because if scientists cannot agree who has Sz (low reliability) then questions of what it actually is (i.e. validity) become essentially meaningless.

VALIDITYSchizophrenia-like disorders: Some indivs show symptoms similar to S-

but do not meet criteria. ICD/DSM- further set of disorders- linked to

above indivs- include- schizophreniform psychosis, schizoaffective disorder, schizotypal disorder, schizoid personality disorder- many variations-difficult to diagnose indiv presenting with S –type symptoms.

Doubt about the validity of some of these classifications- boundary between them blurred.

SYMPTOM OVERLAP some of the Sz symptoms are found in

many other disorders, such as depression and bipolar disorder. Ellason and Ross point out that people with dissociative identity disorder have more Sz symptoms than people diagnosed as being schizophrenic! This affects the validity of the diagnosis.

DIMENSIONAL OR CATEGORICAL DISORDER? Some psychologists believe that Sz-

should be seen as a dimensional disorder, i.e. Degree to which problems are experienced, not simply the presence or absence of such problems.

E.g. People diagnosed with Sz can experience one of its main symptoms ( Hearing voices) – but have developed coping strategies.

SCHIZOPHRENIA AS A MULTIPLE DISORDER Sz sufferers- can present with very different

problems. ICD/DSM- only two very different symptoms

need to be present. No single underlying cause as all people will

display same set of characteristics. Similarly, all people do not respond in the same way to treatments.

Some researchers question the validity of Sz as a diagnosis- suggest abandoning the term, (Bentall, 1993). Each of the symptoms should be seen as a disorder in its own right with its own cause/treatment

DIFFERENTIAL DIAGNOSIS Difficult to define boundaries between S

and other disorders, e.g. Mood disorders, personality and developmental disorders such as autism. People with temporal lobe epilepsy often show similar symptoms to Sz.

Certain prescribed drugs- cause psychotic behaviour- difficult to distinguish between drug- induced psychosis and Sz.

Important for clinician – carry out thorough physical exam and history - for accurate diagnosis. Evidence that early diagnosis and treatment- better long term outcome

DUAL DIAGNOSIS Fairly common to show symptoms of two

mental disorders simultaneously (co-morbidity). S – can be accompanied by depression.

Clinicians make dual diagnosis- appropriate treatment for both disorders

DSM- multi-axial classification system encourages multiple diagnosis

STIGMAS CAN REDUCE VALIDITY A system for diagnosing schizophrenia cannot

be considered accurate if many cases go undiagnosed- due to certain social stigmas and repercussions attached to diagnosing someone with Sz. Although this can occur all over the world it is more likely in a country such as Japan as schizophrenia literally translates to 'disease of the disorganised mind.'

Kim and Berrios (2001) researched this and found that in Japan the idea of a 'disorganised mind' is so stigmatised that psychiatrists are reluctant to tell patients of their condition. As a result only 20% of those with schizophrenia are actually aware of it, while the other 80% are left undiagnosed.

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.

LABELLING

Someone who has suffered 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’ stay with a person.

Schizophrenics risk carrying the stigma of their condition for the rest of their lives.

CULTURAL VARIATIONS  Although Sz occurs across cultures-

finding in USA/UK- more frequently among African American and African- Caribbean pops

Not clear whether it reflects greater genetic vulnerability, psychosocial factors , minority groupings or misdiagnosis.

CULTURAL RELATIVISM Davison & Neale (1994) explain

that in Asian cultures, a person experiencing some 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 abnormalit fact it is not.

CULTURAL RELATIVISM Clinicians could misinterpret cultural

diffs in behaviour and expression as symptoms. Doctors don’t understand Black cultures and misdiagnose Schizophrenia, e.g. some Caribbean cultures believe you should talk to relatives/friends after they have died.

Psychiatrists in Pakistan, China and India- think that the west place too much emphasis on separation of mind and body.

LANGUAGE DIFFICULTIES The clinician might not speak the same

language as the person they are attempting to diagnose.

Certain things can be ‘lost in translation’

This could lead to inappropriate treatment or no treatment at all.

PSYA4: SCHIZOPHRENIATOPIC 1 – ISSUES SURROUNDING CLASSIFICATION & DIAGNOSIS Issue State – Much of the research into the reliability and

validity of the classification systems has been using ethnocentric samples.

Explain – Much of the research carried out on the DSM- IV and the ICD-10 has investigated people diagnosed in Western countries.

Apply – By only using Western samples you cannot get a clear picture of the reliability and validity of the classification systems. The reliability of DSM IV and ICD 10 may be much worse than has been found, which would undermine the use of a classification system at all.

Stretch and Challenge – Psychologists should aim to investigate the reliability of DSM IV (originally formulated in the USA) in other non-Western countries to test the usefulness of a classification system.