A02 classification and diagnosis of schizophrenia Flashcards
Evaluation for or against inter rate reliability?
Against
Who evaluated inter rate reliability
Whaley
What did Whaley find
Found inter rater reliability correlations using DSM-III as low as +.11
Overall conclusion of inter rater reliability evaluation
Not enough evidence to prove that the DSM-III classification system is reliable
Some evidence goes against this notion
What are the four evaluation section in reliability
Inter rater reliability
Unreliable symptoms
Test retest reliability
Comparing DSM-III and ICD
Who evaluated unreliable symptoms
Nicholson and mojtabi
What did Nicholson and mojtabi do/find
Asked psychiatrists in usa to differentiate between bizarre and non bizarre delusions
The psychiatrist had an inter rate reliability of only +.40
Conclusion of unreliable symptoms
The central diagnostic requirement lacks sufficient reliability for it to be a reliable method of diagnosing schizo
Who evaluated test retest reliability
Prescott et al
What did Prescott et al do and find
Analysed test retest reliability of measure of attention and info processing in 14 schizophrenics
Performance if these measure was stable over a 6 month period
Conclusion of test retest reliability
Support view that measure used to diagnose schizo are high in test retest reliability and reliability reliability in general
Who compared dsm and ICD
Cheniaux et al
What did cheniaux do and find
Compared the inter rate reliability of dsm 4 and ICD 10
Schizo more frequently diagnosed according to ICD than dsm 4
Conclusion of comparing dsm with icd
Diagnosis of schizo lacks inter rater reliability and reliability in general if 2 different classification systems are used
What arw the 4 sections of validity
Comorbidity and medical complications
Comorbidity and suicide risk
Eric it may lead to misdiagnosis
Symptoms
Who evaluated comorbidity and medical complications
Weber et al
What did weber et al do and find
Examined hospital discharge records to calculate comorbidity rate
Found 45% of comorbidity linked to psychiatric and behaviour related diagnoses
This affects their prognosis
Conclusion of comorbidity and medical complications
Supports view that validity is decreased due to comorbidity which creates difficulties in the diagnosis of schizo
Poor levels of functioning in schizos may be less to do with their psychiatric disorder and more to do with their untreated comorbidity physical disorders
Who evaluated comorbidity and suicide risk
Kessler et al
What did kessler do and find
Rate of attempted suicide rose from 1% in indvs with schizo alone to 40% in schizos with comorbidity
Conclusion of comorbidity and suicide risk
Indvs with schizo have a high risk of suicide if they have a comorbid disorder
This affects prognosis
Which also affects validity cz it might not be diagnosing what it is wanting to measure, could be due to comorbidity
Who evaluated that ethnicity may lead to misdiagnosis
Harrison et al
What did Harrison et al do and find5
Rate of schizophrenia higher in afro Caribbean groups than for white groups
Conclusion of ethnicity may lead to misdiagnosis
Findings support view that it has low validity
This is because the indvs may have been misdiagnosed due to cultural differences in language and mannerisms and difficulty relating between black patients and white clinicians
Who evaluated symptoms
Ross and ellason
What did ross and ellason find
People with dissociative identity disorder or did have more schizo symptoms than people diagnosed with schizo
Conclusion of symptoms
Some of the symptoms lead to invalid diagnoses cz they’re found in many other disorder
So identification of symptoms of schizo would help
