Schizophrenia Flashcards
(85 cards)
What are the two major systems for the classifications
ICD-11- International Classification of Disease
DSM-5 - Diagnostic and Statistical Manual
Difference between ICD-11 and DSM-5
in the ICD-11 two or more negative symptoms, for one or more months are sufficient for diagnosis
Whereas
in the DSM-5 one positive symptom must be present, for at least one month, for diagnosis
Difference between ICD-11 and DSM-5
The ICD-11 also recognises subtypes of schizophrenia e.g. Paranoid schizophrenia is characterised by powerful delusions and hallucinations whereas catatonic schizophrenia involves problems with a patient’s movement e.g. they may be immobile for long periods of time
However
The DSM-5 does not categorise schizophrenia further into sub-types
What are the positive symptoms
An additional experience beyond those of ordinary existence
Hallucinations
Delusions
What are hallucinations
-Unusual sensory experiences that have no basis in reality
-they can affect any sense
-e.g. auditory hallucinations or visual hallucinations (seeing objects that are not present).
What are delusions
-Irrational/false beliefs that have no basis in reality
-they can make people with schizophrenia behave in ways that make sense to them but may be bizarre to others
Delusions of persecution:- a false belief you are being harassed e.g. by the government
Delusions of control:– a false belief that you are being controlled by something external e.g. by aliens
What are negative symptoms
A loss of usual abilities and experiences
Avolition
Speech poverty
What is Avolition
-Severe loss of motivation to carry out everyday tasks and difficulty to begin or keep up with goal-directed activity
-Andreason (1982) identified three signs of avolition:
-poor hygiene and grooming
-lack of persistence in work or education
-lack of energy
What is speech poverty
-A reduction in the amount and quality of speech
-this is sometimes accompanied by a delay in the sufferers verbal responses during conversation or a lack of fluency
Diagnosis Definition
-The identification of the nature of an illness or other problem by examination of the symptoms
-e.g. Someone reporting hearing voices
Classification definition
-The action or process of classifying something
-the classification of disease according to symptoms
-e.g. A symptom of SZ is hallucinations
The reliability to classifying and diagnosing Sz AO1
-Reliability refers to consistency
-This refers to whether we can gain consistent results when classifying and diagnosing Sz
-Therefore, the extent to which different classification systems agree upon how schizophrenia should be classified and the extent to which two or more health professionals would agree on the same diagnosi
-regardless of time period or culture, measured by inter-rater reliability
The validity to classifying and diagnosis Sz AO1
-Validity refers to accuracy
-the extent to which we are measuring
-what we intend to measure within Sz
-For example, are the classification systems accurately outlining the signs and symptoms of schizophrenia and are health professionals accurately diagnosing schizophrenia
Cheniaux’s research towards reliability and validity of classifying and diagnosing Sz AO1
-Cheniaux asked two psychiatrists to diagnose the same 100 patients using the DSM and ICD
-One psychiatrist diagnosed 26 according to DSM and 44 according to ICD
-The other diagnosed 13 according to DSM and 24 according to ICD. This shows poor inter-rater reliability as one psychiatrist diagnosed almost double the amount than the other psychiatrist
-Moreover, it demonstrates poor reliability in the classification of schizophrenia as both psychiatrists diagnosed almost double the number of patients using the ICD than the DSM
-which also calls in to question the validity of the diagnosis
What factors affect the validity/reliability of classification and diagnosis of Sz
Symptom Overlap
Co-morbidity
Gender bias
Culture bias
What is symptom overlap
-This is where two or more conditions share similar symptoms
-e.g. both schizophrenia and depression involve negative symptoms such as avolition
What is comorbidity
-This is where two illnesses occur at the same time
-Sz is commonly diagnosed with other conditions such as depression/OCD as they share common symptoms eg. lowered motivation/mood
-This is a problem as it means that Sz may not exist as a distinct condition which may lead to misdiagnosis
What is gender bias
Since the 1980s men have been diagnosed with schizophrenia more often than women
-This may be because men are more genetically vulnerable to developing schizophrenia than women
-However, it could be because females with schizophrenia typically function better than men
-being more likely to work and have good family relationships
Evaluation of reliability/validity of classification and diagnosis of Sz limitation-symptom overlap
-One problem of reliability and validity of the classification and diagnosis of schizophrenia is that there is often ‘Symptom overlap’
-This is where two or more conditions share similar symptoms
-e.g. both schizophrenia and depression involve negative symptoms such as avolition
-This questions the validity and reliability of the classification and diagnosis of schizophrenia because an individual may be diagnosed with the wrong disorder
-This is an issue as doctors may not be diagnosing schizophrenia correctly, and therefore individuals may not receive appropriate treatment
-This weakens the validity and reliability in the classification and diagnosis of schizophrenia as it negatively affects its accuracy and consistency
Evaluation of reliability/validity of classification and diagnosis of Sz limitation-comorbidit
-A further problem with the reliability and validity of the diagnosis and classification of schizophrenia is ‘Co-morbidity’
-This is where two illnesses occur at the same time
-e.g. Buckley et al concluded that 50% of patients diagnosed with schizophrenia also have a diagnosis of depression and 23% of patients diagnosed with schizophrenia are diagnosed with OCD
-This questions the validity and reliability of classification and diagnosis of schizophrenia
-because the two conditions may be better seen as one and doctors may diagnose the wrong condition
Evaluation of reliability/validity of classification and diagnosis of Sz limitation-gender bias
-Moreover, another issue with the validity of the diagnosis and classification of sz is Gender bias in diagnosis
-Since the 1980s men have been diagnosed with sz more often than women
-This may be because men are more genetically vulnerable to developing sz than women
-However, it could be because females with sz typically function better than men, being more likely to work and have good family relationships therefore their symptoms may be masked by good interpersonal skills
-This questions the validity and reliability of the classification and diagnosis of sz as women who share similar symptoms
-as men may not receive the same diagnosis as their symptoms seem mild
Genetic theory AO1
-The genetic explanation states that schizophrenia is hereditary and passed on from one generation to the next through genes
-Therefore, a person can be born with a genetic predisposition to sz
-It is believed that several maladaptive ‘candidate’ genes such as PCM1, are involved which increases an individual’s vulnerability to developing sz
-Studies have shown that 108 separate genetic variations are associated in the risk of developing sz
-Gottesman studied 40 twins and found that the concordance rate for monozygotic twins was 48% and only 17% for dizygotic twins
-Therefore, the closer the genetic link to somebody with schizophrenia, the more chance of developing sz
Genetic theory AO3 RTS
-RTS the role of genetics in the development of sz comes from Tierney
-He studied 155 adopted children who had biological mothers with sz and found that they had a concordance rate of 10%
-compared to 1% in adopted children without schizophrenic parents
-This provides significant support for the role of genetics as an explanation of sz as the role of Social Learning Theory
-could not have been a factor as the children were adopted
Neural correlates:- Brain structure/function AO1
-One neural correlate of sz is enlarged ventricles
-A meta-analysis by Raz and Raz found that over half of individuals tested, with sz had increased ventricle size compared to a control group
-Enlarged ventricles are associated with damage to central brain areas and the prefrontal cortex
-this damage is associated with negative symptoms of sz