diagnosis and classification of schizophrenia

Question 1

schizophrenia

Answer 1

a severe mental illness where contact with reality is impaired

Question 2

classification of schizophrenia

Answer 2

• doesn’t have a single defining characteristic, cluster of symptoms, some of which appear to be unrelated
• ICD-10
• DSM-5
• in DSM system one positive symptom must be present for diagnosis whereas two or more negative symptoms are sufficient under ICD
• ICD recognises a range of subtypes of schizophrenia

Question 3

positive symptoms of schizophrenia

Answer 3

additional experiences beyond those of ordinary existence, atypical symptoms experienced in addition to normal experience
-include hallucinations (distorted perceptions) and delusions (irrational beliefs)

Question 4

negative symptoms

Answer 4

involve the loss of usual abilities and experiences

-include avolition (loss of motivation) and speech poverty (reduced frequency and quality of speech)

Question 5

co-morbidity

Answer 5

occurrence of two illlnesses or conditions together, difficult to classify the two disorders seperately

Question 6

symptom overlap

Answer 6

when two or more conditions share symptoms

Question 7

reliability

Answer 7

poor inter rater reliability

• Cheniaux (2009)- has two psychiatrists diagnose 100 patients using both DSM and ICD
• one diagnosed 26 according to DSM and 44 according to ICD and the other diagnosed 13 according to DSM and 24 according to ICD

Question 8

validity

Answer 8

schizophrenia is much more likely to be diagnosed using ICD, suggests schizophrenia is either over diagnosed in ICD or under diagnosed in DSM -poor validity

Question 9

co-morbidity evaluation

Answer 9

2 or more conditions occur together, if conditions occur together or questions the validity of their diagnosis, might be a single condition

• Buckly-50% of patients with schizophrenia also diagnosed with depression or substance abuse, PTSD in 1/3 and OCD in 1/4
• poses and challenge for classification and diagnosis
• diathesis stressmodel

Question 10

symptom overlap evaluation

Answer 10

schizophrenia and bipolar disorder both have positive symptoms, under ICD patient may be diagnosed schizophrenic but under DSM diagnosed as bipolar

Question 11

gender bias in diagnosis

Answer 11

Longnecker (2010)- reviews studies and concluded since 1980s, men have been diagnosed much more often than women

• may be because men have a genetic vulnerability to it
• however it appears women are able to function better than men

Question 12

cultural bias in diagnosis

Answer 12

positive symptoms such as hearing voices may be more acceptable in African cultures because of cultural beliefs