Issues Surrounding Classification And Diagnosis Of Schizophrenia Inc Reliability And Validity

Question 1

Reliability definition

Answer 1

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

Question 2

Validity definition

Answer 2

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

Question 3

Reliability studies

Beck et al

Rosenhan

Answer 3

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”

Question 4

Validity

Answer 4

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

Question 5

Cultural variation

Answer 5

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

Question 6

The myth of mental illness - Szarsz

Answer 6

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