Lesson 3 - reliability and validity in diagnosing schizophrenia Flashcards
co morbidity
the extent when two or more conditions exist simultaneously
Swets- 12% of schizophrenia patients have OCD , 1% have schizophrenia and 2.5% OCD - problems diagnosing schizophrenia not OCD
weaknesses of validity of diagnosing schizophrenia
w- schizo patients w co morbid illnesses are excluded from research . findings can’t be generalised and may be invalid
w- some symptoms are similar to substance abuse and most schizo Ps abuse thus not reliable diagnosis
culture bias
a)when patients from ghana, india, and the US were interviewed, the US participants reported the most negative experiences associated with the voices. thus culture has an influence on the reliability of diagnosing skiz
b) asian cultures praise ppl for not showing pain and distress thus they don’t ask for help and are therefore not included in studies and stats. its the opposite for arab culture, therefore culture bias
weakness of culture bias
w- cultural relativism. the psychologist may not understand the patients symptoms correctly. in some african cultures, they say they can hear god speak to them , if in western countries- they would be skiz. this is inaccurate
strength of culture bias
+ support of cultural relativism
afro-carribean ppl have low immunity to the flu. if ur mum has the flu whilst in second trimester , 88% chance you’ll get skiz. therefore, africans more likely to be skiz than white. cultural vulnerability
gender bias AO1
males have an earlier onset
healthy adult behaviour is based on men in DSM
therefore DSM is gender biased and accuracy of diagnosing skiz in women is low
gender bias weakness
w- when P described as male 56% psychologists said it was skiz, when describing same symptoms as female only 20% diagnosed w skiz
w-validity of diagnosis is questioned bcs females develop skiz 4-10 years after men. males and females are vulnerable to diff types of skiz
symptom overlap AO1
some symptoms of skiz are also found in other mental illnesses
-shared symptoms could lead to an invalid and incorrect diagnosis
what illnesses overlap with skiz
bipolar
depression
strength of symptom overlap
clinicians should conduct a brain san to check for deterioration of grey matter . patients w bpd don’t have reduced grey matter
weakness of symptom overlap
w- skiz patients diagnosed with other illness - they don’t get the care they need. increases suicide rates
w- inter rater reliability is low. there is a 54% agreement between 2 psychiatrists in terms of diagnosing skiz. suggests that 2 psychiatrists can give a diff diagnosis to same patient
being sane in insane places - rosenhan
study on psychiatrists distinguishing schizophrenics from non skiz
8 sane patients to 12 separate hospitals - claimed to hear voices
after admittance, pseudo Ps stopped showing symptoms
all Ps but one given diagnosis of skiz
35/118 genuine Ps suspected the pseudo Ps
pseudo Ps stayed in the hospital for 7-52 days
sane in insane places conclusion
psychiatrists cannot detect sane from insane and diagnosis of skiz is unreliable
rosenhan extra info abt pseudo Ps
hospital staff were told that pseudo Ps would seek addmittance in the next 3 months
- out of 193 patients , 43 were confidently identified by hospital staff as pseudo and 23 were suspects
- rosenhan sent no pseudo Ps and all patients were genuine
weaknesses of sane in insane places
w-diagnostic procedures have improved since this exp was done . DSM and ICD are now used. to ensure reliability now, 2 psych need to both agree patient is skiz
w- to increase validity, before diagnosing , psych should consult a senior
strength of sane in insane places
if someone behaves skiz, its good that the hospital admits them instead of turning them away if they acc needed the help.
