Reliability in Schizophrenia

Question 1

What is reliability?

Answer 1

Consistency of measure

Question 2

What is diagnostic reliability?

Answer 2

A particular diagnosis must be repeatable, and refers to the level of agreement on diagnosis by different psychiatrists across time and culture

Question 3

What are the ways of measuring diagnostic reliability? Explain what they are

Answer 3

Test-retest (if we do the diagnosis again, we should get the same result) and Inter-rater reliability (2 people looking at the same person using the same classification system should both diagnose/not diagnose someone)

Question 4

Explain the research into the test-retest method in diagnostic reliability - + the A03 point

Answer 4

Read et al (2004) showed a concordance rate of only 38% for test-retest reliability (there’s only a 30% chance that the person will be diagnosed again on a retest sometime later)
A03 - This suggests there is low test-retest reliability which is a weakness as it shows that there is a high level of misdiagnosis of schizophrenia

Question 5

Explain the research into inter-rater in diagnostic reliability - + the A03 point

Answer 5

Chiniaux et al (2009) - two psychiatrists independently diagnosed 100 patients both using the DSM and ICD classification system
They found that one psychiatrist diagnosed 26 with the DSM and 44 with the ICD and the other diagnosed 13 using the DSM and 24 with the ICD
A03 - Shows there is poor inter-rater reliability between psychiatrists which is a weakness for the diagnosis of schizophrenia