Schizophrenia Flashcards
(39 cards)
Schizophrenia
A type of psychosis characterised by a profound disruption of cognition and emotion so that contact with external reality and insight are impaired.
Classification
Organising symptoms into categories based on which symptoms cluster together in sufferers i.e. what are the symptoms of schizophrenia?
How common is schizophrenia?
The most common psychotic disorder, affecting 1% of the population at some point.
Most commonly diagnosed in males, city-dwellers and lower socio-economic groups.
Diagnosis
Deciding whether someone has a particular mental illness using the classifications.
Hallucinations
Disturbances of perception in any of the senses - either have no basis in reality or are a distortion of something that is real.
Delusions
False beliefs not based in reality
Positive symptoms
Atypical symptoms experienced in addition to normal experiences
Negative symptoms
Atypical symptoms that represent a loss of a usual experience
What is DSM-5 system?
-used in USA
-two of the positive symptoms must be present for diagnosis
-only one if delusions are bizarre
-only one if hallucinations consist of a voice with running commentary or two voices conversing
-continuous disturbances for at least a month
-at least one major area of function (work) must be below the previous level
What is ICD-10 system?
-used in Europe
-two or more negative symptoms
-one positive symptom
Symptom overlap
Occurs when two or more conditions share symptoms. Where conditions share many symptoms this calls to question the validity of classifying the two disorders separately.
Co-morbidity
The occurrence of two disorders or conditions together, e.g. a person has both schizophrenia and a personality disorder. Where two conditions are frequently diagnosed together it calls into question the validity of classifying the two disorders separately.
Osario et al. (2019) found inter-rater reliability of […] for DSM-5.
+0.97 (consistently applied)
Osario et al. (2019) found test-retest reliability of […] for DSM-5.
+0.92 (consistently applied)
Validity is the extent …
to which schizophrenia is a unique syndrome with unique characteristics, signs and symptoms (so whether it measures what it intends to measure).
Serper et al. assessed …
patients with co-morbid schizophrenia and cocaine abuse, or either on its own.
Serper et al. found …
Despite there being considerable symptom overlap in patients with schizophrenia and cocaine abuse, it was actually possible to make accurate diagnoses.
Serper et al. findings suggest …
schizophrenia
Co-morbidity is not a significant issue
Ketter points out …
schizophrenia symptom overlap
misdiagnosis due to symptom overlap can lead to years of delay in receiving relevant treatment, during which time suffering and further degeneration can occur, as well as high levels of suicide
Ketter’s found …
schizophrenia symptom overlap
Symptom overlap can have serious consequences and focusing on fixing this issue could save money and lives.
Ketter’s findings suggest …
Symptom overlap is a significant issue
Bukely et al found …
co-morbidity schizophrenia
Around half of patients with a diagnosis of schizophrenia also have a diagnosis of depression (50%) or substance abuse (47%). PTSD also occurred in 29% of cases and OCD in 23%.
Buckley et al findings suggest …
Co-morbidity is a significant (over 20%) issue
General evidence for cultural bias in schizophrenia diagnoses…
African-Americans and English people of Afro-Caribbean origin are up to 10 times more likely to be diagnosed with schizophrenia. Given that rates in Africa and the West Indies aren’t high (ruling out a genetic vulnerability), the diagnosis seems to be the result of cultural bias.