Download 01. bias in diagnostic systems

PY4: Abnormal Psychology: Bias in Diagnostic Systems
1. Issues of Bias in Diagnosis (pg 228-230)
What do we mean by diagnosis?
What is a bias?
A bias with regards to a diagnostic system (such as the DSM IV) means that certain people or groups of
people are more likely to be classed as having a particular disorder than other types of people. The main
issue to bear in mind when looking at these biases is to ascertain whether
1. the bias resides in the system being used to make the diagnosis (meaning that some groups tend to
be misdiagnosed as having an illness when they don’t),
2. Or whether there is an actual difference in the rates of
mental illness between different groups of people (in
which case, the diagnostic system is accurate).
In this topic we will be looking at three different types of bias
 Cultural Bias
 Gender Bias
 Social Class bias and Age Bias (in brief)
From your research, what is the DSM IV?
For more info, see box on pg 231.
Culture bias
What was your answer for question 4 (classification of mental illness)
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There appears to be a major bias in diagnosis with regards to people of African descent. This is particularly
prevalent with major disorders such as schizophrenia.
What did Cochrane and Sashidharan (1995) find? (pg 230) ______________________________________
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While this evidence suggests that a bias in diagnosis exists, it does not give us any information about the
nature of this bias. Is there a bias in the diagnosing, or is there a genuine difference in the rates of
schizophrenia between those of African decent, and others?
Possible explanations for culture bias: over diagnosis due to inadequate diagnostic methods
Bias in the diagnostic tools used: one possible explanation could be that the diagnostic tool (such as the
DSM IV or the ICD) is inherently culturally biased. These two classification systems were developed in the
USA and Europe, and as such may overemphasis a western concept of ideal mental health, ignoring the role
of cultural factors. This can lead to two problems:
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PY4: Abnormal Psychology: Bias in Diagnostic Systems
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Things that may be classed as symptoms of mental illness in one culture
(hearing voices for example) may be regarded as normal in other cultures.
This could lead psychologists to misinterpret what is regarded as a social
norm in one culture as a sign of mental illness, leading to over-diagnosis of
disorders.
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The same illness could manifest itself differently in different cultures.
o For example Ebigno (1986) pointed out that symptoms of depression
vary from culture to culture. In the West it is characterised by feelings
of worthlessness and hopelessness and loss of interest in most activities. In Nigeria however,
people often complain of burning sensations in the body and crawling sensations in the head
or legs, and a bloated feeling.

It could also lead to ignoring some genuine mental illnesses which do not occur in Western culture.
For example
o Koro; this disorder involves extreme anxiety that the penis or the nipples will recede into the
body, and possibly cause death. It is found in south east Asia.
o Ghost Sickness: the main symptom is an excessive focus on death and on those who have
died. This is common in North American native tribes.
o Amok: a period of time spent brooding, followed by a violent outburst. Mainly found in
Malaysian men.
These illnesses may be misinterpreted by Western psychologists, unfamiliar with these culturebound syndromes possibly leading to a false diagnosis of a more familiar disorder.
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What about bias in the psychological tests? (pg 230) ______________________________________
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Bias in the person who is doing the diagnosing:
Lewis (1990): 139 psychiatrists were shown an individual written case history.
They were asked to make a judgement on the treatment that the patient should
have. They were also required to predict whether criminal proceedings should be
instigated as a result of the behaviour described. Some psychiatrists were told
that it was a black Afro-Caribbean patient, while others were told that it was a
white patient. The symptoms for both were identical.
 He found that when the patient was described as black, the psychiatrists
were more likely to recommend drug treatment, and the patient was also
seen as more violent and criminal. This suggests that mental health
professionals can be biased in their judgement by social stereotypes.
However, an issue with this research is _______________________________________________________
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Possible explanations for culture bias: genuine differences in rates of mental illness
Stress of being a minority/immigrant:
It may be that there is a genuine difference between different cultural groups, and that the
bias in diagnosis is only reflecting the real difference between these groups.
One possible explanation is that the stress associated with being an ethnic minority or an
immigrant leads to higher stress levels, which could trigger mental illness. Immigrants
generally are of a lower social class, and have to adapt to living in a foreign culture, and
may lack communication skills due to the language barrier. Littlewood (1980) argues that
what might be judged insane by some mental health practitioners may actually be a
legitimate and understandable response to disadvantage and racism.
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PY4: Abnormal Psychology: Bias in Diagnostic Systems
This would seem like a neat explanation. However as Littlewood and Lipsedge
(1989) point out, the vast majority of immigrants to the UK in recent history have
been white, yet the bias in diagnosis only applies to black immigrants.
Another issue with this theory is that the rates of serious mental illness are higher for
British born black people rather than their parents, or recent immigrants (Littlewood
1989). We would expect this group of individuals to have a lower rate of mental illness if it was the stress of
being an immigrant that triggered the mental illness.
Genetic factors:
Another possible explanation is that the bias is due to genetic factors. It may be that
people of African descent have a genetic vulnerability to developing certain types of
mental illness. Therefore it would have nothing to do with culture or social status or stress.
The bias is simply reflecting that certain races of people have an increase prevalence of
the genes for a particular illness.
Again, while this seems like a nice explanation, the research evidence does not back it up.
In 1979 the World Health Organisation (WHO) conducted a study of the rate of
schizophrenia in Europe, America, Africa and Asia. If black people had a genetic
vulnerability to schizophrenia, what would we expect to find?
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However, the results are quite different. What did Nazroo (1997) find? ______________________________
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Also, how does Littlewood (1989) above contradict the idea of genes? _____________________________
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Vitamin D:
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PY4: Abnormal Psychology: Bias in Diagnostic Systems
Sum up what the article suggests about the possible cause of the diagnostic bias? Could it explain all of the
research looked at so far? What does it suggest about culture bias?
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Revision Check: Can you...
 Describe what the culture bias in diagnosis is? (AO1)
 Explain how this bias may be due to inadequate diagnostic methods (AO1)
 Provide and evaluate research which supports this theory (AO2)
 Explain how this bias may be due to genuine differences in rates of mental illness (AO1)
 Provide and evaluate research which supports this theory (AO2)
Gender bias
What was your answer for question 6 (gender bias in mental illness)
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There are clear gender differences with regards to different mental illnesses. For example,
90% of sufferers of anorexia nervosa are female. What possible reasons cold there be for
this?
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Robins et al (1984) considered gender differences in the
lifetime occurrence of various mental illnesses across
three American cities. As we can see from the results
here, men are much more likely than women to be
diagnosed with alcohol abuse, whereas women are more
likely to be depressed or have a phobia.
Disorder
Alcohol abuse
Anti-social conduct
Major Depression
Specific phobia
Lifetime prevalence
Men
Women
27%
4%
5%
1%
2%
8%
4%
9%
In the UK, women are more likely than men to be admitted to hospital for treatment with depression than
men. Walker (1994) reported that women with depression outnumber men between two to six times. There
appears however to be no gender bias for the occurrence of bi-polar disorder or schizophrenia.
However, this gender bias in diagnosis is quite recent. Cochrane (1995) argues that earlier in the twentieth
century, men were much more likely to be admitted to hospital than women.
But as with cultural bias, these statistics tell us that there is a bias in diagnosis, but does not give us the
cause of this bias. Do actually suffer more with certain types of mental illness, or are they just more likely to
be diagnosed with an illness.
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PY4: Abnormal Psychology: Bias in Diagnostic Systems
Possible explanations for gender bias: over diagnosis due to inadequate diagnostic methods
Worell and Remer (1992) identified four possible reasons why there may be a gender bias. These explain
the gender bias in terms of an over-diagnosis by therapists.
1. Disregarding environmental context: the focus in diagnosis is on the symptoms rather than the
individual’s circumstances. This may produce a gender bias if female patients have to cope with
more difficult circumstances than male patients.
o What sort of difficult circumstances might women have which do not apply to men?
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2. Differential diagnosis on the basis on gender: similarly to ethnicity (above) a patient’s symptoms
may be interpreted differently depending on their gender, leading the therapist to exaggerate the
number of men and women with disorders which conform to the gender stereotype
o Could this explain the statistics above? ___________________________________________
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Ford and Widiger (1989) presented therapists with written case
studies of two patients. One had symptoms of anti-social personality
disorder (reckless and irresponsible behaviour: a typical “male” illness);
the other had histrionic personality disorder (excessive emotionality
and attention seeking: a typically “female” illness). Each patient was
either labelled as male or female. The descriptions were the same.
Disorder
Anti-social
personality disorder
Histrionic
personality disorder
Correct diagnosis
Male patient Female patient
40%
20%
30%
80%
Worell and Remer (1992) would argue that these results
show that women and men are diagnosed in different ways,
and that bias lies in with the person doing the diagnosing.
However, could there be an alternative explanation?
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Could the criticism for Lewis (1990) be applicable here? _________________________________________
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3. Therapist misjudgement: traditional sex role stereotyping may increase the chances that the
therapist will detect symptoms of submissiveness or dependence in female patients, and
aggressiveness in male patients.
o Broverman et al (1981) asked health care professionals to outline the key features of a
mentally healthy adult, a healthy male, and a healthy female. The description of the healthy
male was very close to the description of the healthy adult, and included words such as
“independent, decisive and assertive”. The description of the healthy female on the other
hand included terms such as “submissive, dependent and emotional”. This suggests that
there exist gender stereotypes about expected female and male behaviour.
o Does this research still have validity? _____________________________________________
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PY4: Abnormal Psychology: Bias in Diagnostic Systems
4. Theoretical orientation: the therapist may have various theoretical
biases relating to gender, and these may distort the process of
assessment and diagnosis.
o For example ______________________________________
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 Another possible explanation for bias is that much of the research behind the classifications of mental
illness has used male participants. If health and normality are defined with respect to the sex role
stereotype of men, then the symptoms of mental illness may be based on the deviations from this
stereotype. If this were the case, it would discriminate unfairly against women. The results of
Broverman (above) could be seen as evidence for this.
 The results of Broverman might imply some other reason for why there is a gender bias in diagnosis:
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Possible explanations for gender bias: genuine differences in rates of mental illness

An often proposed cause of the high level of depression in women is hormones. A
woman’s hormones fluctuate during the month, as well as childbirth and the
menopause and this may possibly explain why women are more prone to
depression.
o However Weissman et al (1977) found that whilst there is some evidence
of hormone contribution, it cannot completely account for the large
differences between men and women.

However, the fact that the gender difference in diagnosis really only exists for
depression suggests that there might be a genuine difference between men and women. If the bias
lay purely in the diagnosis, we would expect women to have higher rates for other mental illnesses
such as the related bi-polar disorder.
Revision Check: Can you...
 Describe what the gender bias in diagnosis is? (AO1)
 Explain how this bias may be due to inadequate diagnostic methods (AO1)
 Provide and evaluate research which supports this theory (AO2)
 Explain how this bias may be due to genuine differences in rates of mental illness (AO1)
 Provide and evaluate research which supports this theory (AO2)
General things to consider (pg 231)
Regardless of whether we are looking at gender bias, culture bias, or social class bias (see next page), you
might think what the point of having a diagnostic system if it is full of biases?
The DSM and ICD do not even agree with each other, for example, different descriptions of schizophrenia.
What does this suggest? __________________________________________________________________
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However, what happens to the DSM and ICD periodically? _______________________________________
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What can you recall from Rosenhan (year 12) about labelling? How can this be overcome?
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What is a publication bias, and why is this an issue for diagnosis? ________________
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Any more relevant points:
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