Classification & Diagnosis

Question 1

Schizophrenia

Answer 1

• Type of psychosis - severe mental disorder characterised by profound disruption of cognition & emotion so that contact with reality is impaired
• Affects language, though, perception, emotions, sense of self
• Most common psychotic disorder - 1% of population
• Many end up homeless or hospitalised
• 1/5 recover completely - no cure, only symptom relief
• Peak incidence onset: 25-30 years old

Question 2

Classification

Answer 2

Organising symptoms into categories based on which symptoms cluster together in sufferers

Question 3

Diagnosis

Answer 3

Deciding whether someone has a particular mental illness using the classifications

Question 4

Positive Symptoms

Answer 4

• Things that are added, that normal people don’t have
• Hallucinations = seeing/hearing
• Delusions = false cognition
• Disorganised Speech = word salad
• Catatonia = completion issues

Question 5

Negative Symptoms

Answer 5

• Things that people have lost - present for at least a year
• Avolition = less motivation, when options are present
• Alogia = loss of fluency/productivity
• Affective Flattening = reduced emotion
• Anhedonia = loss of physical excitement

Question 6

DSM-V Diagnosis Criteria

Answer 6

• 2< symptoms for at least 1 month
• Some signs must last for continuous period of at least 6 months
• Schizoaffective disorder, biopolar, depressive disorder with psychotic features have been ruled out
• Substance use and other medical conditions ruled out
• All ASD presentations ruled out

Question 7

Reliability Problems

Answer 7

• Symptoms overlap with other disorders
• Comorbidity - which came first or which is the main cause of illness

Question 8

Validity Problems

Answer 8

• Gender Bias in diagnostic criteria
• Cultural differences - ethnocentrism

Question 9

Being Sane in Insane Places: Rosenhan (1973)

Answer 9

• Covert participant observation in 5 states
• Students (N=7) reported only hearing a ‘dull thud’ - not a symptom according to DSM-II
• All diagnosed SZ and hospitalised - 100% Type 1 error rate
• Medicated & treated - not allowed to leave until uni intervened
• High inter-rater reliability - low intenal validity

Question 10

Being Sane in Insane Places: Follow up study

Answer 10

• Rosenhan later phoned hospitals and said he was sending more fake patients - he never actually did
• Over the next 2 weeks, 21% of patients were labelled ‘pseudopatients’ and released - type 2 error

Question 11

Evaluation of Diagnostic Systems

Answer 11

• Whaley et al: Inter-rater reliability was 0.11 (0.8 needed for reliable result)
• Gender bias = Diagnosis - M=56%, F=20%
• Comorbidity issues - problems in application/treatment