schizophrenia: classification and diagnosis Flashcards
(26 cards)
define schizophrenia
Schizophrenia is characterised by a profound disruption of cognition and emotion, which affects language, thought, perception and
sense of self.
what are the 2 manuals used to diagnose SZ
- DSM-5
- ICD-10
How does ICD-10 characterise SZ
requires 2 or more positive/negative symptoms
how does DSM-5 characterise SZ
One positive symptom: delusions, hallucinations or speech disorganisation must be present for six months or one month if “active”
which manual includes a range of types of SZ
ICD-10 > For example paranoid schizophrenia is characterised by power delusions and hallucinations but few other symptoms and **catatonic schizophrenia is characterised by a disturbance of movement. **
what are positive symptoms
These symptoms are something that an individual experiences in addition to what we would consider ordinary existence
what are negative symptoms
These symptoms are when an** individual has lost an aspect of what we would consider ordinary existence** – the individual’s daily life experiences have been reduced in some way
state 2 positive symptoms
- hallucinations
- delusions
state 2 negative symptoms
- speech poverty
- avolition
define delusions
Bizarre beliefs that seem to be real to the person with schizophrenia, but they are not real. Sometimes these can be paranoid (e.g. “everyone is out to kill me”). They may also involve inflated beliefs about that person’s power (e.g. “I am the Queen”)
define hallucinations
Bizarre, unreal perceptions of the environment. These are usually auditory (hearing things e.g. voices) but can also be visual (e.g. seeing things) or tactile (e.g. feeling bugs crawling over your skin)
define speech poverty
characterised by not being able to express complicated ideas and speaking very slowly. This is thought to indicate slowing or blocked thoughts.
define avolition
The reduction of, or inability to, initiate and persist in goal-directed behaviour (e.g. sitting in the house for hours and doing nothing all day instead of going to work).
define diagnosis
deciding what disorder a person has
define classification
how a disorder is defined
what would valid classification and diagnosis mean
- Classification: The criteria is accurately measuring schizophrenia and not another disorder
- Diagnosis: Accurately labeling the patient as having schizophrenia when they do
what would reliable diagnosis mean
Diagnosis: When the criteria is used by another psychiatric, they come to the same conclusion and diagnosis.
explain the issue with classifcation of SZ
the DSM
5 and ICD 10 both define schizophrenia differently > we do not know if we are accurately measuring schizophrenia > If they were defining
schizophrenia accurately we should have one universal definition
explain the issue with diagnosis of SZ
the ICD 10 and DSM 5 would not produce the same diagnosis > inter-rater reliability would be low Different manuals may produce a different diagnosis for the same patient> As a result, some countries may overdiagnose or underdiagnose schizophrenia
AO3: subjectivity of diagnosis
The diagnosis and classification of schizophrenia is invalid. Rosenhan showed that 11/12 people could fake their way in to a psychiatric
hospital and that staff were too quick to judge someone as schizophrenic. This suggests the diagnosis of schizophrenia is subjective. Even with the
symptoms of schizophrenia set out, the behaviour of an individual (i.e. the patient) is always open to some interpretation.
WEAKNESS as this implies the diagnosis system is invalid Additionally, this suggests that the classification of schizophrenia is not actually measuring schizophrenia.
AO3: lacks reliability
The diagnosis of schizophrenia lacks reliability
Cheniaux et al had two psychiatrists independently diagnose 100 patients using both DSM and ICD. They found one psychiatrist diagnosed 26 with DSM and 44 with ICD. The other psychiatrist diagnosed 13 with DSM and 24 with ICD. This suggests the inter-rater reliability was poor. Both psychiatrists did not come to the same conclusion for the same patients.
WEAKNESS as the diagnosis of schizophrenia lacks reliability and is made subjectively.
COUNTER: However, research published later demonstrates that the diagnosis for schizophrenia has excellent reliability. Osorio et al found an inter-rater reliability of +.97 and test retest of +.92 when pairs of interviewers assessed 180 individuals used the DSM-5.
This suggests that there is inconsistent research regarding the reliability of the diagnosis of schizophrenia
AO3: cultural bias
According to DSMVI and ICD 10, symptoms of hallucinations can warrant a diagnosis of schizophrenia. However, this criteria does not take into account differences in culture. African Americans and English people of Afro-Caribbean origin are several times more likely than White people to be diagnosed with schizophrenia. Since,
statistics of schizophrenia are not particularly high in Africa or the West indies,this is not due to genetic vulnerability. But instead due to culture bias.
WEAKNESS because symptoms such as hearing voices may be more acceptable in African cultures due to their belief in communication with their ancestors. Therefore people are more likely to acknowledge and report such experiences. If the
individual is speaking to a psychiatric from a different culture, they are likely to see such experiences as irrational and could result in a diagnosis of schizophrenia, when in reality the patient does not suffer from schizophrenia.
Define comorbid
individuals may have 2 separate conditions where one might hide or contribute to the other one (and thus mutually reinforce the other).
define symptom overlap
the criteria from the ICD and DSM is not clear
enough (symptoms are shared between conditions), meaning conditions are confused as one in the same.
* eg Someone with bipolar is diagnosed as schizophrenic.
