AQA A Level Psychology Schizophrenia notes

SCHIZOPHRENIA

Diagnosis and Classification of Schizophrenia 

Schizophrenia: a mental illness where the individual has lost touch with reality. As a result, the individual does not have insight into their disorder which means that they cannot recognise their symptoms. It affects approximately 1% of the population and many receive treatment after 1-episode after leading normal lives.  

Diagnosing schizophrenia: according to DSM-5, schizophrenia is characterised by delusions, hallucinations, disorganised speech and behaviour and other symptoms include social/occupational dysfunctions.  

DSM-5 states that: for a diagnosis, symptoms must be present for 6 months and a patient must show at least one month of active symptoms. DSM-5 requires an individual to show at least 2 symptoms. 

Positive symptoms: symptoms which are an addition to an individual’s behaviour.  

• Delusions: this is a distorted belief. An individual might be feeling as if they don’t have any control over their thoughts and feelings.  

• Hallucinations: here, voices are the most common symptoms. These voices don’t exist but feel real for the individual. These tend to be very repetitive voices often muttering the same words to the individual multiple times during the day.  

• Disorganised speech: mixed-up thought processes affect a patients’ speech resulting in muddled sentences where they often mix up topics in a sentence, so it doesn’t make sense. This is often referred to a “word salad.” 

Negative symptoms: involve losses of emotion and pleasure to one’s behaviour. 

• Speech poverty (Alogia): this symptom involves a reduction in the quality and amount of speech in schizophrenia. The person will speak infrequently, and their speech will be influent, and their sentences will be incoherent just like Broca’s and Wernicke’s aphasia.  

• Avolition: this symptom involves a reduction in goal-directed behaviour. Andreason (1982) identified 3 signs of avolition: poor hygiene and grooming, lack of persistence in work and education and lack of energy.  

In order to get a diagnosis of Schizophrenia:  

1. DSM-5: one positive symptom must be present  

1. ICD-10: 2 or more negative symptoms must be present  

 

 

 

 

 

 

 

 

 

Reliability in diagnosis and classification of Schizophrenia 

Reliability: focuses on the consistency of a measurement. This refers to the classification system: DSM or ICD.  

Inter-rater reliability: whether the same clinician uses the same classification system with the same patient give the same diagnosis. If they do, this means that the classification system is reliable.  

Test-retest reliability: whether the same clinician uses the same classification system with the same patient at 2 different time periods and whether it gives the same diagnosis. If it does, then the classification system is reliable. 

 

Why might there be issues with reliability: 

Co-morbidity: this refers to when 2 or more conditions occur together. Patients with schizophrenia often have disorders such as bipolar or anxiety disorder alongside each other. Co-morbidity happens because some symptoms are…