Reliability and Validity in Schizophrenia Diagnosis Flashcards
What is the book called that doctors use to diagnose mental disorders?
DSM-5
To be diagnosed with schizophrenia, what do patients need to display?
DAt least 2 of the main symptoms for at least 6 months.
What does it mean if a study is internally valid?
The study measures what it claims to be measuring.
What symptoms should a person display to be diagnosed with schizophrenia, according to the DSM?
At least two main symptoms for at least\6 months.
Azriel faked some symptoms of a common disorder, described these symptoms to the doctor and received a diagnosis. He then saw a different doctor, who gave a different diagnosis.
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Explain why Azriel’s diagnosis was neither reliable nor valid.
Reliability of diagnosis requires diagnoses to be consistent between doctors, or between patients with the same symptoms. As Azriel’s two doctors were not consistent, his diagnosis is not reliable. Azriel does not have a disorder at all, so his diagnosis was not valid either. Validity means that the disorder is correctly diagnosed, which in Azriel’s case it was not.
Inter-rater reliability is when multiple people..?
Make the same measurement, to see how similar their measurements are.
Which of the following statements are true about the reliability of a diagnosis of schizophrenia?
Researchers use inter-rater reliability to assess the reliability of a diagnosis of schizophrenia.
CIn 2005, researchers found that they were 81% similar.
DA diagnosis of schizophrenia is becoming more reliable over time.
If the volunteers were told to pretend they were hearing voices, which symptom of schizophrenia would this be?
Hallucinations.
The doctors in Rosenhan’s study gave the volunteers a diagnosis of schizophrenia when they were actually mentally healthy. What do these diagnoses lack?
validity
Which of the following statements are true about Rosenhan’s method?
DRosenhan conducted an observation study.
ERosenhan tested how long it took doctors to declare that the volunteers were healthy.
BRosenhan got 8 volunteers, who pretended to have schizophrenia, admitted into hospital.
Which of the following statements are true about Rosenhan’s results?
BIt took the doctors between 7 and 52 days to realise the diagnoses were wrong, and that the volunteers were healthy.
DThe study showed that the diagnosis of schizophrenia can lack validity.
What is cultural bias?
Researchers misrepresent the differences between cultures
The unwritten rules for how all members of a social group are expected to behave are called
social norms
What type of cultural bias it is when someone assumes that other cultures behave the same as their own?
Ethnocentric bias.
Which of the following are consequences of cultural bias in diagnosing disorders?
ADoctors might be more likely to diagnose someone from another culture with a mental disorder.
ETwo doctors with different cultural backgrounds might give the same patient a different diagnosis.
Cultural bias means that doctors might be
Cultural bias means that doctors might be more likely to diagnose someone from another culture with a mental disorder. Also, the same patient might get a different diagnosis, depending on the cultural background of their doctor. This reduces the reliability of the diagnosis.
If a doctor incorrectly diagnoses a patient with schizophrenia, what would this diagnosis lack?
validity
When doctors diagnose schizophrenia, they rely on the
When doctors diagnose schizophrenia, they rely on the social norms of their own culture to decide whether a patient’s behaviours match symptoms of schizophrenia. This means they are more likely to diagnose schizophrenia in patients who are from a different culture to the doctor’s own. So, cultural bias reduces or decreases the validity and reliability of a diagnosis.
In Cochrane’s study, why were Afro-Caribbean people living in Britain being overdiagnosed with schizophrenia due to cultural bias?
Doctors in Britain were judging the patients using the social norms from their own culture.
Which of the following statements about Cochrane’s study are correct?
The overall rate of schizophrenia was similar in the Caribbean and in Britain.
Cochrane conducted a review comparing the number of people diagnosed with schizophrenia in the Caribbean and in Britain.
Cochrane concluded that this was because of cultural bias by British doctors.
Afro-Caribbean people were 7 times more likely to be diagnosed with schizophrenia in Britain than in the Caribbean.
Dr Craig has over-exaggerated the differences between men and women’s behaviours, therefore he has shown…
Alpha bias, gender bias.
If the doctors ignore real differences between men and women, then they are displaying…
gender bias
Patients with the same symptoms might get different diagnosis depending on their gender, reducing the
Patients with the same symptoms might get different diagnosis depending on their gender, reducing the reliability of the diagnosis.
What method was used in Loring and Powell’s study?
AThey gave male and female doctors identical descriptions of a patient’s symptoms.
CThey varied the patient’s gender.
When the patient was described as female
When the patient was described as female, 20 % of doctors diagnosed the patient with schizophrenia.
When the patient was described as male, 56% of doctors diagnosed the patient with schizophrenia.
This indicates there may be alpha bias in the diagnosis of schizophrenia.
Cultural bias is when researchers
Cultural bias is when researchers misrepresent the differences between cultures, and therefore assumes that the patients behaviour is more abnormal because it does not fit with local social norms. Dr Ellis is displaying this because she assumes the two cultures are similar.
How does cultural bias affect the validity of a diagnosis?
The doctor might diagnose someone with a disorder who doesn’t actually have a disorder.
Explain how cultural bias affects the reliability of a diagnosis.
Cultural bias means that doctors might be more likely to diagnose someone from another culture with a mental disorder. This means that the same patient might get a different diagnosis, depending on the cultural background of their doctor, which would therefore reduce the reliability of the diagnosis because it would not be consistent.
Which of the following are true about Cochrane’s study?
Cochrane concluded that the study provided evidence of cultural bias by British doctors.
BCochrane conducted a review of doctors’ consultations.
CCochrane compared the rate of schizophrenia diagnosis in the Caribbean and in Britain.
Which of the following statements correctly explain how gender bias affects validity of diagnosis?
If the criteria used to diagnose schizophrenia over or under-exaggerate the differences between men and women, then they won’t correctly identify schizophrenia in all men and women
Complete the following statements about Loring and Powell’s study:
When the patient was described as female,
% of doctors diagnosed the patient with schizophrenia.
When the patient was described as male,
% of doctors diagnosed the patient with schizophrenia.
The results indicate an bias in diagnoses of schizophrenia.
When the patient was described as female, 20 % of doctors diagnosed the patient with schizophrenia. When the patient was described as male, 56% of doctors diagnosed the patient with schizophrenia. The results indicate an alpha bias in diagnoses of schizophrenia.
What does it mean if illnesses are comorbid?
Two or more illnesses occur together in the same person
If the doctors are more likely to diagnose different disorders when a patient has comorbid illnesses, what does this decrease?
Reliability
If the criteria for diagnosing schizophrenia are incorrect, what will the diagnosis lack?
validity
Given how comorbid they are, it is possible that depression and schizophrenia aren’t two separate disorders at all - they might just be part of the same illness. Therefore what might the criteria used to diagnose schizophrenia lack?
validity
Buckley investigated how many schizophrenic patients had a comorbid mental disorder.
He found that: 50% of patients had depression and s chizophrenia, 47 % of patients had an addiction and schizophrenia, and 23 % of patients had OCD and schizophrenia.
When Aretha experiences false beliefs during periods of mania, what is this called?
Delusions.
If the criteria incorrectly diagnoses someone as having schizophrenia, what can we say is lacking from the diagnosis?
validity
Which of the following statements are true about symptom overlap?
The symptoms of schizophrenia considerably overlap with the symptoms of other disorders.
Patients might be diagnosed with the wrong disorder, reducing the validity of the diagnosis.
EDifferent doctors might diagnose a patient with a different disorder, reducing the reliability of the diagnosis.
How could symptom overlap reduce the reliability of diagnosis?
Different doctors might look at the same symptoms and give a different diagnosis.
How could the symptom overlap in Ellason and Ross’s study reduce the validity of diagnoses in the study?
The criteria used to diagnose schizophrenia don’t enable doctors to correctly distinguish between schizophrenia and dissociative identity disorder.
What did Ellason and Ross compare to study symptom overlap in schizophrenia?
Symptoms of schizophrenia patients with those of dissociative identity disorder patients.
What did Ellason and Ross’s study find?
Patients with dissociative identity disorder displayed more schizophrenic symptoms than patients with schizophrenia.
How does comorbidity affect validity of diagnosis?
When a patient has comorbid illnesses, the doctor might only diagnose one of the two illnesses.
DIf two illnesses are often comorbid, this suggests that the criteria for diagnosing the two illness might be incorrect - they might not actually be two separate conditions.
How does comorbidity affect reliability of diagnosis?
If a patient has a comorbid illness, then doctors are more likely to ignore some of the symptoms, therefore different doctors may give the same patient different diagnoses. This therefore reduces the reliability of diagnosis.
Which condition is comorbid in 50% of schizophrenia patients?
Depression
Which researcher(s) showed that 50% of patients with schizophrenia also have depression?
Buckley.
Dr Webber conducted a study with 100 doctors. She divided them into pairs and gave each pair a different description of a patient displaying symptoms of schizophrenia. Then, she asked each doctor in the pair to diagnose the patient and compared their diagnosis with the diagnosis of the other doctor in the pair.
What was she testing and why
Inter-rater reliability is if more than one doctor diagnoses the same disorder in a patient with the same symptoms. Dr Webber is testing this because she gave the same list of symptoms to
2 different doctors to see if they gave the same diagnosis.
