diagnosis & classification

• schizophrenia

  -a disorder characterised by impaired reality - contact & insight with reality is impaired

  -example: psychosis
• diagnosis & classification

  -diagnosis: process of identifying & deciding the disorder someone has

  -classification: identifying a cluster of symptoms that happen together

  -diagnosis & classification are interlinked
• ICD-10; DSM-5

  -ICD-10: used in Europe to classify & diagnose mental disorders. Schizophrenia is based on negative symptoms e.g., speech poverty. Symptoms must be present for at least a month.

  -DSM-5: used in America to classify & diagnose. Need 2 symptoms present for at least a month, one needs to be a positive symptom e.g., delusions.
• positive symptoms

  -are additional to someones regular behaviour

  -hallucinations: visual or auditory, can be related to current event or made up

  -delusions: irrational beliefs: delusions of grandeur e.g., believing they're Jesus; delusions of persecution e.g., believing someone is following them

  -disordered thinking: believing thoughts are being interfered with: insertions; withdrawals; broadcasting

  -disorganised speech
• negative symptoms

  -taking away from someones normal behaviour

  -avolition: lack of motivation, very apathetic, 3 signs: poor hygiene; lack of persistence; lack of energy

  -speech poverty: changes in pattern of speech, reduced amount and quality of speech

  -flattening of affect: don't show cues of emotions e.g., facial gestures
• comorbidity AO3 point

  -more than one disorder existing alongside one another/a primary diagnosis

  -when two disorders exist together e.g., schizophrenia & personality disorder

  -can cause issues with the validity of classification as they're diagnosed together. Psychiatrists may not be able to tell the difference between the two e.g., severe depression looking like schizophrenia

  -Buckley et al (2009): around 1/2 of people diagnosed with substance abuse also have a depression diagnosis. Schizophrenia commonly occurs with other disorders, it is co-morbid
• symptom overlap

  -when disorders share the same symptoms

  -schizophrenia symptoms overlap with those of other disorders which can make it hard to classify & diagnose the disorder despite the use of positive & negative symptoms to try and make it more valid

  -Ellason & Ross (1995): people with dissociative identity disorder (DID) had more schizophrenic symptoms than people with diagnosed schizophrenia

  -diagnosis of disorders can differ depending on which classification is used (ICD or DSM)

  -Ophoff et al (2011): found a genetic overlap between schizophrenia & bipolar disorder (3 gene locations on genome overlap)
• AO3

  strength(s):

  -reliability: Osorio et al - diagnosed 180 people with DSM-5 in pairs of interviewers. Inter-rater reliability of +.97; test-retest of +.92, a strong positive correlation which shows the use of diagnostic tools.

  
  

  weakness(es):

  -Lack of criterion validity: the different tools have different criteria. DSM-5 = under diagnosis; ICD-10 = over diagnosis. The criteria can also lead to misdiagnosis which impact labels. Are labeled as SCZ, can become a self-fulfilling prophecy & master status. Does not help psychology achieve its aim of helping people.

  -gender bias: diagnoses more men than women - men = 9x more likely to be diagnosed. Women less diagnosed as women are said to function better. Can cause psychological harm. Doesn't fulfil the aim.

  -culture bias - African-Americans = hearing voices & seeings things are not seen as abnormal but are in western society. Rates of SCZ diagnosis = less in Africa. Diagnostic tools are ethnocentric & can't be generalised.