reliability and validity of diagnosis

Question 1

Spitzer and Williams (reliability) -

Answer 1

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

Question 2

Ward (1962) reliability -

Answer 2

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

Question 3

Brown (2002) reliability +

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: patient

Answer 4

patient factors- info they give

Question 5

Factors that affect the reliability of diagnosis: clinician factors

Answer 5

clinician factors- subjective with the classification system, gathering insufficient info Ahmed Aboraya et al (2006) found draw attention to many factors which prevent practitioners from making reliable diagnoses as they dont have time for structured interviews and interfere with development of therapeutic rapport

Question 6

Factors that affect the reliability of diagnosis: classification system

Answer 6

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 7

Pederson (2001) +

Answer 7

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

Question 8

what is concurrent validity

Answer 8

comparing evidence from diagnostic tests to see if they agree

Question 9

aetiological validity

Answer 9

exists when the diagnosis reflects known causes

Question 10

predictive validity

Answer 10

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 11

Factors that affect validity of diagnosis: patient factors

Answer 11

Patient factors- may not disclose all relevant info as they may be embarrassed or ashamed so clinician won’t get an accurate diagnosis

Question 12

Factors that affect validity of diagnosis: clinician factors

Answer 12

Clinician factors- implicit bias either one holds as their beliefs may effect diagnosis

Question 13

Factors that affect validity of diagnosis- classification

Answer 13

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 14

Littlewood (1992) validity -

Answer 14

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

Question 15

Mason et al (1997) validity -

Answer 15

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