[S] Classification and diagnosis Flashcards
What is schizophrenia defined as?
A loss of contact with reality.
What are the five subtypes of schizophrenia?
Catatonic, paranoid, disorganised, residual and undifferentiated.
How long must a patient suffer with a disturbance in lifestyle before diagnosis?
6 months.
What are positive symptoms and examples of them?
Positive symptoms reflect an excess or distortion of normal functions, and include hallucinations, delusions, disorganised speech and thoughts and disorganised behaviour and movement.
What are negative symptoms and examples of them?
Negative symptoms reflect a loss of normal functioning, and include diminished emotional response, avolition and absence of social functions.
How can inter-rater reliability differ?
Depending on the classification system used.
What did Beck et al (1962) find?
A correlation of 0.54 between experienced clinicians’ diagnoses of 153 patients.
What did Soderburg (2005) find?
A correlation of 0.81 between clinicians’ diagnoses.
What could the differences in the results of Beck and Soderburg be due to?
Different versions of the DSM which changed the characteristics and requirements of schizophrenia.
What has been removed in the latest version of the DSM?
Subtypes of schizophrenia.
What can also affect inter-rater reliability?
The diagnostic process, diagnoses are made through a semi-structured interview with the patient from which symptoms are inferred from information given and from the behaviour of the patient.
What did Mojtabi and Nicholson (1995) ask clinicians to do?
They asked them to distinguish between delusions which were bizarre or non-bizarre, and found a correlation of 0.40 in senior clinicians.
What factors of the patient can make an accurate diagnosis difficult?
The patient may be forgetful or confused or unwilling to give the clinician information.
What did Whaley (2001) find?
Whaley found inter-rater reliability to be as low as 0.11 when white clinicians were diagnosing African-American patients, reflecting issues of cultural mistrust and misunderstanding of those of another culture.
If diagnostic definitions of schizophrenia are valid what should we see?
Those diagnosed with the same order should be similar, and those not should be different (descriptive validity).
What does Read (2004) note?
If 2 of 5 key symptoms need to be present for a diagnosis of schizophrenia, there are 15 ways which patients can meet the criteria without having anything in common.
Where are symptoms of schizophrenia often found?
In other disorders such as schizoaffective disorder or bipolar depression.
What did Ellason and Ross (1995) find?
Patients with dissociative identity disorder have more schizophrenic symptoms than some people diagnosed with schizophrenia.
What does diagnostic overlap make possible?
Incorrect diagnoses and more erroneous diagnoses.
If diagnoses of schizophrenia are valid, what should patients do?
React similarly to the same treatment.
How does the outcome of treatment vary?
1/3 experience ongoing problems, 1/3 experience occasional relapse and 1/3 make a full recovery.
If diagnoses of schizophrenia are valid, what should clinicians be able to do?
Distinguish between those with schizophrenia and those without it.
Describe Rosenhan’s (1973) study.
8 volunteers presented themselves to different mental hospitals all claiming to hear voices. They were admitted and acted normally after this. They were all diagnosed with schizophrenia, except one, and it took 53 days for one of the hospitals to release the last volunteer.
Why might clinicians treat everyone who appears to be schizophrenic?
It is better to act on a ‘better safe than sorry’ basis as it protects the public and the individual.
