Issues Surrounding Classification And Diagnosis Of Schizophrenia Inc Reliability And Validity Flashcards
Reliability definition
Each time a classification system is used it should produce the same result
Consistency clinicians agree = “inter rater reliability”
Two or more researchers must agree when a person should or shouldn’t be diagnosed
Validity definition
Overall appropriateness of system - how it groups those diagnosed
Predictive validity - assumes if diagnosed, they will respond to treatment eg drugs/therapy - if they do not this casts doubt on the diagnosis
Reliability studies
Beck et al
Rosenhan
Beck et al - 2 psychiatrists, 154 cases - inter-rater reliability as low as 54%
BUT due to nature of illness patients have radically different answers as can’t differentiate between reality
Retrospection may mean events have been forgotten or exaggerated
Rosenhan - 8 pseudo patients admitted to psychiatric hospital with diagnosis of schiz (except one who had a mood disorder) after reporting they repeatedly heard a voice saying “thud”, “hollow”, “empty”
None of the staff suspected they were fake but 1/3 of the patients did
Eventually discharged as schizophrenics in remission - 7-52 days later
Context of psych hospital made normal beh unnatural - one kept a diary and accused of “pathological writing beh”
Validity
Schizophrenic like disorders - not an all or nothing condition like DSM/ICD suggests - schiz symptoms could be schizoid personality disorder for example
Multiple disorders? - only two potentially v different symptoms needed for diagnosis and therapies v differing in results - some believe each symptom should be treated as its own disorder
Dimensional/categorical - classification should relate to degree of symptoms not simply their presence - some hear voice but deal successfully with them
Dual diagnosis - fairly common to be diagnosed with more than one disorder - schiz often accompanied by depression - important dual diagnosis ensures individual receives appropriate treatment for each
Cultural variation
Davison and Neale - in Asian cultures if an individual experiences emotional turmoil but does not show it, they are praised and rewarded
In certain Arabic cultures, the outpouring of emotion is understood and encouraged - without this info, in western culture they may be regarded as abnormal
Translation - interaction required between health professional and potential patient - if not able to describe detailed symptoms you risk misdiagnosis
The myth of mental illness - Szarsz
Argues labelling behaviour/emotions as illness is a problem as all are part of the human condition but once labelled as “illness” they become destructive - presents motivation