What is Schizophrenia?
Thought process disorder characterised by disruption to perceptions, emotions and beliefs
There is still no single agreed definition. It's thought that it isn't a single disorder, but that it has lots of subtypes.
Acute = sudden onset, behaviour changes rapidly over a few days
Chronic = gradual deterioration in mental health over a long period of time
Positive symptoms = abnormal behaviours are 'added on'
- Auditory hallucinations (hearing voices)
- Delusions (believing things that aren't true)
- Thought control (believing that thoughts are being controlled or broadcasted)
- Visual hallucinations (seeing things that aren't there)
- Incoherent/disorganised speech
- Distorted thinking
Negative symptoms = normal behaviours are 'taken away'
- Social withdrawal
- Depressive symptoms (lack of energy or interest)
- Impaired emotions
Issues with Classification and Diagnosis
Main classification systems in use are the DSM-IV and ICD-10. There are differences between the two systems which reduces inter-rater reliability since different clinicians may use different systems.
- DSM requires symptoms to be present for 6 months. ICD requires symptoms for 1 month.
- DSM mentions 5 subtypes, ICD mentions 7.
- DSM is considered more reliable because it asks for more specific symptoms
The inconsistencies mean that a patient may not recieve the best method of treatment, or may be wrongly diagnosed.
(consistency of diagnosis)
Interpretation: The DSM states that only one positive symptom needs to be present for diagnosis if it is 'bizzare'.. this leads to problems with reliability
- Research has found inter-rater reliability correlations of just 0.40 for differentiating between 'bizzare' and 'non-bizzare'.
Inter-rater reliability: Beck et al (1962) found that agreement on diagnosis of 153 patients between 2 psychiatrists was just 54%. Could be due to vague diagnosis criteria.
Culteral bias: Different classification systems are used in different countries lowering the reliablity. Also, ethnic minorities are more likely to be diagnosed as schizophrenic.
- Copeland et al (1971) gave the same description of…