reliability & validity of schizophrenia

Created by

iqra

Cards (24)

7 types of issues for diagnosis of sz?
reliability
inter rater reliability
culture bias
validity
comorbidity
symptom overlap
gender bias
issues affecting reliability?
reliability
inter rater reliability
culture bias
issues affecting validity?
validity
comorbidity
symptom overlap
gender bias
conclusion for all reliabilty?
if schizophrenia is diagnosed incorrectly this could be problematic as it may be over/under diagnosed by psychiatrists meaning that patients will be incorrectly labelled as schizophrenic or not diagnosed meaning they wont receive the treatment they need
issue of reliability?
level of agreement/consistency on diagnosis of schizophrenia over time given no change in symptoms
example for reliability?
when person may be diagnosed by their doctors having schizophrenia symptoms on one occasion & later receive different diagnosis by same doctor
diagnosis would not be reliable over time
consequence of low reliability?
may be misdiagnosed
reiger 2013 found reliability of diagnosis of sz had correlation of +0.46
consistency over time is weak positive
2 seperate occasions patient with sz may be diagnosed differently next time
means someone wont receive treatment they need/incorrect treatment
issue of inter rater reliability?
level of agreement/consistency on diagnosis of schizophrenia by different psychiatrists
whether 2 independent assessors give same diagnosis of schizophrenia to same patient
example of inter rater reliability?
when person is diagnosed by 1 doctor as having schizophrenia but another doctor diagnoses them with bipolar disorder
diagnosis of schizophrenia would not be reliable between clinicians
consequence of low inter rater reliability?
may have missed diagnosis/be misdiagnosed
nilsson 2000 found inter rater reliability for diagnosis of sz was 60% meaning that theres 40% likelihood that 2 different doctors will diagnose same patient with different disorders
someone wont receive treatment they need/incorrect treatment
issue of culture bias?
culture of patient/clinician affects diagnosis so lacks reliability
doctors use own cultural norms to interpret patients
if patients culture accepts hallucinations as being normal this affects diagnosis/likelihood to admit to symptoms
example of doctors culture bias?
copeland 1971 gave description of patient to 134 uk & US clinicians
69% US diagnosed schizophrenia
2% UK diagnosed schizophrenia
shows that schizophrenia is more likely to be diagnosed in US than uk
example of patient culture bias?
interpretation of auditory hallucinations
seen as acceptable in african culture due to culture beliefs about communication with ancestors but when viewed by doctor in uk may be seen as symptom of schizophrenia
consequence of persons ethnic group/doctors culture affecting diagnosis?
luhrman interviewed 60 adults with sz
20 each in ghana/india/us
each asked about voices heard
africans & indians described voices as playful/offering advice
US more likely to describe voices violent/hateful
suggested harsh & violent voices so common in west may not be inevitable feature of sz - lacks consistent characteristics
leads to unreliable diagnosis means patient may not be actually have sz
just aspects of culture thats normal influencing behaviour
conclusion for all validity?
if schizophrenia is not being diagnosed accurately this could be that patients being diagnosed with wrong disorder
it may not be a distinct disorder
issue of validity?
extent to which schizophrenia is unique syndrome with characteristics, signs & symptoms
looks at extent to which classification system being used is accurate reflection of illness experienced by patient
example of validity?
to what extent would 1 patient be diagnosed with schizophrenia using ICD classification tool & also be diagnosed with schizophrenia using DSM classification tool
diagnosis therefore lacks validity
consequence of invaild diagnosis?
leads to incorrect treatment
rosenhan 1973 studied validity of diagnosis for pseudo patients admitted to psychiatric hospitals
8 healthy confederates arrived complaining of 1 single symptom - heard voice saying empty/hollow/thud
after admission behaved normally
11 patients - sz
1 patient - manic depression
leads to misdiagnosis
poses wider consequence for patient & society
inaccurately labelled - not get correct support
economic implications for NHS spending money on wrong treatments
issue of comorbidity?
when 2 disorders co-exist at same time in same individual so patient gets diagnosed with schizophrenia & another disorder
example of comorbidity?
patient being diagnosed with schizophrenia & substance abuse or schizophrenia & depression
diagnosis of schizophrenia lacks validity as it can lead to confusion about which disorder is being diagnosed
consequence of comorbidity?
leads to misdiagnosis
buckley 2009 found that 50% of people with sz also have depression
47% people with sz also have substance abuse
sz commonly occurs alongside other mental illnesses & disorders
hard for clinician to decide which is main disorder to treat
patient may receive meds for wrong disorder/not get treatment for right thing
side effects of treatment could have negative impacts on symptoms
issue of symptom overlap?
where symptoms for schizophrenia are also classified as symptoms for another disorder
share/similar symptoms
example of symptom overlap?
same patient could be diagnosed with both bipolar disorder or schizophrenia because they have symptoms of avolition & delusions
consequence of symptom overlap?
patient diagnosed with wrong disorder
number of symptoms of sz also symptoms of different disorders - bpd
clincian may diagnose patient with sz when suffereing from different disorder
ketter 2005 found misdiagnosis can lead to delay in receiving relevant treatment during which time suffering & further degeneration can occur
getting treatment for wrong disorder - detrimental effects causing them to be worse