reliability and validity of diagnosis

Question 1

Spitzer and Williams

Answer 1

reviewed diagnosis and suggested that experience psychiatrists only agree on diagnosis 50% of the time

Question 2

Ward

Answer 2

studied 2 psychiatrists diagnosing the same patient and found disagreement occured due to inconsistency of info provided by patient 5%. psychiatrists interpretation of symptoms 32.5%, inadequacy of classification system 62.5%

Question 3

Brown

Answer 3

tested reliability and validity of DSM IV and diagnosis for anxiety and found them to be good to excellent

Question 4

Factors that affect the reliability of diagnosis

Answer 4

patient factors- info they give
clinician factors- subjective with classification system,
classification system- DMS-5 clear set criteria which increase the reliability if 2 or more clinician use this standardised set of criteria they are more likely to agree- improving inter-rater reliability the new ICD 11 correlates well with the DMS 5

Question 5

Pederson

Answer 5

found 71% of psychiatrists agreed with the ICD-10 definition of depression when assessing 116 patients indicating inter-rater reliability

Question 6

what is concurrent validity

Answer 6

comparing evidence from diagnostic tests to see if they agree

Question 7

aetiological validity

Answer 7

exists when the diagnosis reflects known causes

Question 8

predictive validity

Answer 8

cause of the disorder is known and can be applied to person so a diagnosis can be checked against the outcome to see if it’s valid

Question 9

Factors that affect validity of diagnosis

Answer 9

Patient factors- may not disclose all relevant info as they may be embarrassed or ashamed so clinician won’t get an accurate diagnosis
Clinician factors- implicit bias either one holds as their beliefs may effect diagnosis
Classification- *Cochrane et al** blames classification system used in Britain as it takes on an Eurocentric Bias so don’t take into account normal behaviours of other cultures

Question 10

Littlewood

Answer 10

Q the international validity of the DSM-IV as it makes assumptions of the nuclear family that are not applicable to others

Question 11

Mason et al

Answer 11

diagnosis of schizo of ICD-10 has good predictive validity accurate diagnosis for future functioning for 99 people with schizo