classification systems: DSM

Question 1

what is the dsm?

Answer 1

• describes symptoms and features of over 300 mental and behavioural disorders arranged into 22 categories
• made in US
• first used after WW2 and has been revised number of times

Question 2

what is in section 1?

Answer 2

offers guidance about using the new system

Question 3

what is in section 2?

Answer 3

details the disorders and is categorised according to our understanding of underlying causes and similarities between the symptoms

Question 4

what is in section 3?

Answer 4

suggestions for new disorders that require further investigation
and includes info about impact of culture on presentation of symptoms and way they’re communicated

Question 5

how do you make a diagnosis?

Answer 5

• gather info using observation but much will be based on unstructured interviews.
• there are also structured interviews- Beck Depression Inventory
• process includes ruling out disorders which dont match symptoms before deciding which is ‘best fit’
• simple disorders can take 10 minutes by GP to diagnose and complex cases can take weeks

Question 6

how is reliability assessed?

Answer 6

• Spitzer introduced Cohen’s kappa to improve reliability of DMS-III
• statistic refers to proportion of people who receive same diagnosis when re-assessed at later time or by different clinician
• felt 0.7 showed good agreement

Question 7

how is validity assessed?

Answer 7

• over years disorders have been removed and added to different versions of DSM
• validity of these labels sometimes criticised

Question 8

what is descriptive validity?

Answer 8

when 2 people with same diagnosis show similar symptoms

Question 9

what id aetiological validity?

Answer 9

when they share same causal factors

Question 10

what is concurrent validity?

Answer 10

when clinician uses more than one method to reach the same diagnosis

Question 11

is the dsm reliable?

Answer 11

-field trials show high level of agreement between clinicians and disorders
EG. Reiger found for PTSD kappa values ranged from 0.60 to 0.80 (very good)
and 7 other diagnoses (including SZ) had kappa values of 0.40 to 0.60
- clinicians have adapted to criteria changes and symptom required to make diagnosis

Question 12

weakness of reliability of dsm?

Answer 12

-levels of agreement have decreased over years
EG. Cooper explains DSM 5 task force classified levels as low 0.2-0.4 as acceptable
one of least reliable diagnoses was major depressive disorder - 0.28
DSM might be less reliable than previous versions and diagnoses might have been by mistake or missed

Question 13

BUT….

Answer 13

others explain that clinicians working in DSM5 trial were told to ‘work as they usually would’ to mirror normal practice but DSM-III used carefully screened tests and clinicians given training
SO, unsurprising DSM-5 trials had lower levels of reliability

Question 14

how strong is the validity of the DSM?

Answer 14

-Kim-Cohen demonstrated concurrent validity of conduct disorder through interviewing children and their mother, observing anti social behaviours and using questionnaires from teachers.
- specific risk factors (male, low income) were common in many cases> aetiological validity
- 5 year olds with CD more likely to display educational and behavioural problems at 7> predictive validity
SO, accurate diagnosis could reduce adult mental health problems

Question 15

weakness with validity?

Answer 15

-labels don’t tell us about causes
publication of DSM-5 led storm of criticism from professionals who claimed psychiatric disorders don’t tell us about cause
argument is circular