reliability and validity in diagnosis and classification of schizophrenia

Question 1

inter-rater reliability

Answer 1

little evidence that DSM is routinely used with high reliability with mental health clinicians. Whaley(2001) found that interrater reliability correlations in diagnosis as low as 0.11. This illustrates that there is a lack of objective measures for assessing schizophrenia compared to other illnesses

Question 2

reliability- cultural differences in the diagnosis of schizophrenia

Answer 2

the ethnic cultures hypothesis predicts that ethnic minority groups experience less distress associated with mental disorders because of the protective characteristics and social structures that exist in their cultures. Support of this comes from Brekke and Barrio who did a study on 184 individuals who were diagnosed with schizophrenia. this sample was drawn from two non-white minority groups and a majority group. They found that the majority group were more symptomatic then members of the minority groups.

Question 3

validity- support for gender bias.

Answer 3

Loring and Powell found evidence of gender bias when diagnosing patients. 290 randomly selected patients had to read two vignettes of patients behaviour and then asked to provide a judgement. when the patient was described as a man or no info was given about gender they were diagnosed 56% of the time, whereas when they were described as female they were only diagnosed 20% of the time. However this bias was not as evident among female psychiatrists suggesting the diagnosis of the patient is influenced by the gender of the clinician.

Question 4

validity- consequences of co-morbidity

Answer 4

Weber et al(2009) looked at 6million hospital discharge records and found evidence of many co-morbid and non-psychiatric diagnoses. patients with a primary diagnosis of schizophrenia were also diagnosed with other medical problems. it can therefore be concluded that the nature of the diagnosis of a psychiatric disorder is that patients receive a lower standard of medical care which therefore adversely affects the prognosis(development) of the patients schizophrenia