Reliability And Validity In Diagnosis + Classification

Question 1

What is meant by reliability?

Answer 1

Results are consistent

Question 2

How is reliability measured?

Answer 2

• Measured in 2 ways;
  -Test retest reliability
• inter-rater reliability

Question 3

What is meant my test-retest reliability?

Answer 3

• The same person does the same test at a later date and gets a very similar result.

Question 4

What is inter-rater reliability?

Answer 4

• Person A is observed by 2 different researchers and ty determine wether a patient is diagnosed
  -Improve mis by having near clarification categories of what me observed are looking out for

Question 5

Test re text reliability evidence

Answer 5

Read et al
37% concordance rate of re-test reliability
69% diagnosed with schizophrenia in America but only 2% in UK

Question 6

What Read et al suggest?

Answer 6

• this suggests that the diagnosis of schizophrenia has never been fully reliable.

Question 7

Inter-rater reliability research evidence.

Answer 7

Cheniaux
Had 2 psychiatrists independently diagnose 100 patients using both DSM and I CD criteria
Inter rater reliability was poor
Psychiatrist diagnosing 26 according t0 DSM and 44 according to ICD
Other diagnosing 13 according to DSM and 24 according to ICD

Question 8

Evaluation
What is considered to be more reliable.? And why?

Answer 8

DSM considered to be more reliable than ICD
Because symptoms outlined for each category are more specific

Question 9

Evaluation
What does evidence generally suggest about reliability of diagnosis?

Answer 9

Evidence generally suggests that reliability of diagnosis has improved al classification system have been updated.

Question 10

Evaluation
Advantage to having classification systems?

Answer 10

• They provide practitioners with a common language permitting communication of research ideas and findings which may ultimately lead to a better understanding of the disorder and development of effective treatments
• so support can be given after diagnosis

Question 11

evidence to say that diagnosis of schizophrenia is unreliable ?

Answer 11

Rosenhan
- conducted a study in which pseudo patients were all given consistently the same incorrect diagnosis of schizophrenia
- but after the premise of the study was revealed, new pseudo patients were sent to hospital but were not admitted although they presented the same symptoms

Question 12

Rosenhan A03
- how can the rate of admission of pseudo patients be explained ?

Answer 12

• it is not usual for people to fake insanity to gain admission
• expectation effect
  means that the doctors expected them to be ill and looked for evidence to verify it
• which clouded their judgement

Question 13

AO3 limitation
- being diagnosed as schizophrenic is a sticky label

Answer 13

• it is difficult to remove such a label
• and removing it may have serious consequences

Question 14

AO3 Rosenhan limitation
- old study

Answer 14

• method of diagnosing schizophrenia has changed and is a lot more different than before
• criteria in DSM has changed
• that diagnostic is outdated

Question 15

Validity AO3
- what is predictive validity ?

Answer 15

• if diagnosis leads to successful treatment, then diagnosis is valid

Question 16

Validity AO3
- why is predictive validity low >

Answer 16

• because different sufferers experience such a wide range of symptoms

Question 17

AO3 validity
- what does Bentall claim about diagnosis ?

Answer 17

• claims that the diagnosis of schizophrenia says nothing about its cause
• just gives people a label
• implies diagnosis is invalid