Classification of Schizophrenia Flashcards
(12 cards)
Schizophrenia
A type of psychosis, a severe mental disorder characterised by a profound disruption of cognition and emotion so that contact with external reality is impaired.
This affects a person’s language, thought, perception, emotions and even their sense of self
Classification
Organising symptoms into categories based on which symptoms cluster together in suffered
Positive symptoms (2 examples)
Atypical symptoms experienced in addition to normal experiences
• Hallucinations - disturbance of perception in any sense. False perceptions that have no basis in reality or are distorted perceptions of throngs that are
• Delusions - firmly held irrational beliefs that have no basis in reality
Delusions of persecution
Delusions of grandeur
Delusions of control
Delusions of reference
Negative symptoms (2 examples)
Atypical experiences that represent the loss of a usual experience - diminution or loss of normal functioning
•Avolition - a lack of purposeful, willed behaviour. No energy, sociability affection or attempt at personal hygiene
• Speech poverty - brief verbal communication style of quality and quantity of verbal responses
Diagnosis (tools used)
Deciding whether someone has a particular mental illness using classifications
The DSM 5 and ICD 11 are methods used to diagnose and classify schizophrenia
Reliability (2 types)
Levels of agreement/consistency on the diagnosis of schizophrenia by different psychologists across time and cultures. The stability of the diagnosis over time given no change in symptoms
• Inter-rater reliability - measure of how two observers agree. Whether a decisions is consistent between observers
• Test-retest reliability - clinicians must be able to reach the same conclusions at two different points in time
Reliability evidence - (2 Neg 1 Pos)
BECK - review of 153 patients diagnosed by multiples doctors found only 54% concordance rate between doctors assessments
Suggests low inter-rater reliability in diagnosis of schizophrenia: issue because it suggets many have been misdiagnosed and aren’t receiving proper treatment
CHENIAUX - 2 psychiatrists diagnosed 100 people using DSM and ICD criteria
Inter-rater reliability was poor:
• 1- 26 from DSM and 44 from ICD
• 2- 13 from DSM and 24 from ICD
OSARIO - excellent reliability of +.97 and test-retest reliability +.92
Validity
Concerns whether we accurately assess what we are trying to assess. Whether a person really has the disorder when diagnosed or that disorder is real with clear and unique symptoms
Symptom overlap (1pos 1neg)
Where symptoms classify under multiple conditions
SERVER- assessed patients with co-morbid SCZ and cocaine abuse
Despite there being considerable symptom overlap it was possible to make accurate diagnoses
Suggests symptom overlap doesn’t affect the ability of diagnoses
KETTER - points out misdiagnosis due to symptom overlap can lead to years of delay in receiving relevant treatment. During this time suffering continues including high rates of suicide in SCZ patients
Co-morbidity (1 neg)
The extent that two or more conditions occur together (commons among SCZ patients)
BUCKLEY - following co-morbid rates
• Depression - 50%
• OCD - 23%
Complicates treatment plans and suggests the original diagnosis of SCZ may be less valid or an error
Culture bias (reliability/validity AND evidence)
Validity: psychiatrists may impose their own cultural standards (imposed etic) and are biased to what is normal for thei culture (ethnocentrism). Any deviation from cultural norm may be SCZ
Reliability: suggests there isn’t agreement or consistency of diagnosis across cultures. Patients can display the same symptoms but receive different diagnosis due to ethnic backgrounds
ESCOBAR - pointed out that white psychiatrists tend to over-interpret the symptoms of black people during diagnosis and factors such as cultural differences in language/mannerisms could be causing this
African Americans are several times more likely to be diagnosed with SCZ - positive symptoms such as auditory hallucinations may be more acceptable in African culture due to a belief in communication with ancestors
LUHRMANN - 60 adults- 20 Ghana, 20 India and 20 USA asking about the voice they heard. Those in Ghana reported positive experiences with the voices but no Americans did.
Suggests the harsh, violent voices so common in the West may not be inevitable feature of SCZ
Gender bias (reliability/validity and evidence)
Reliability: if patients are seen by different clinicians they might receive diagnosis - lacks inter-rater reliability
Validity: if clinicians fail to consider these issues, correct treatment and support cannot be provided
BRAVERMAN - clinicians in USA equated mentally healthy adult behaviour with ‘male behaviour’. Tendency for women to perceived as less mentally healthy
LORING AND POWELL - 290 psychiatrists: 56% gave diagnosis of SCZ. When described as female 20% gave diagnosis
This bias did NOT occur amongst female psychiatrists
