Transcript dsm valid and reliable

The DSM –
how valid and reliable is it as a tool
for diagnosis?
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Dad
Purchased
Most
Extraordinary
Glasses
DSM – a multi-axial system
• Axis I
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Disorders, clinical and mental eg
schizophrenia
Axis II Personality (underlying) including
mental retardation
Axis III Medical and Physical conditions
Axis IV Environmental factors
Axis V Global functioning
Evaluation of the DSM
Strengths:
• It’s the best attempt at diagnosis that there is and
it allows a common diagnosis
• There are studies which support its reliability and
validity
Weaknesses
• It can be considered a way of labelling people
whose behaviour we see as “different”
• In the US some people argue by inventing mental
illnesses psychiatrists can make more money
Goldstein (1988)
use for RELIABILITY
• she re-diagnosed 199 patients using DSMIII,
originally diagnosed using DSM–II; some
differences....... But 85% consistent = Test-retest
reliability
• she asked two other experts to re-diagnose a
random sample of 8 of the patients using the case
histories with all indication of previous diagnoses
removed – she found a high level of
agreement/consistency of diagnosis = Inter rater
reliability
Stinchfield (2003) recent!!
use for validity
• Diagnosis of pathological gambling (severe enough
habit to inhibit and interfere with daily functioning)
• 803 men and women from general population of
Minnesota and 259 men and women on gambling
treatment programme
• Questionnaire using 19 items from DSM IV criteria for
pathological gambling
• Questionnaire results were able to help researches to
correctly sort the gamblers from the non-gamblers.- so
the DSM is doing what it should .... It’s VALID!
Lee (2006)recent!
Use for VALIDITY and CROSS-CULTURAL
• Aimed to reveal whether the DSM criteria for
diagnosing ADHD would be useful for Korean children
• Assessed 18 ADHD criteria in DSM IV
• Questionnaire given to 48 primary school teachers.
• 1663 children were rated – large sample
• There was a match between the features of ADHD
outlined in the DSM and the responses to the
questionnaires, an ADHD test and teacher assessments
• but the match was not as good for girls as it was for
boys .... Maybe a validity problem
Kim-Cohen et al (2005)
use for validity
• Longitudinal study looking at conduct disorder in
over two thousand 5 year olds
• Children’s mothers were interviewed and the
teachers were asked to complete postal
questionnaires about conduct disorder symptoms
(from DSM IV) observed in last 6 months
• The children who received the diagnosis were
also more likely to display behavioural and
educational difficulties at age 7 = Predictive
validity
Rosenhan (1973)
use for reliability and validity
• Because the diagnosis was the same across all
12 of the hospitals presumably using the
current DSM at the time, we could say this
shows the DSM to be reliable
• Because the diagnosis of healthy people was
schizophrenia, if they were using the DSM this
means it lacks any validity
Evaluation of validity issues
STRENGTHS
• The DSM has been shown to be valid across a
variety of studies covering a range of different
conditions
• Because it is reliable it is likely to be valid too
• Much work has been done to increase its
validity as it has been rewritten
WEAKNESSES
• It is hard to diagnose people who are suffering
from more than one condition (co-morbidity)
when using the DSM
• It can be considered to be reductionist to break
down a condition into a series of symptoms, so
we shouldn’t over concentrate on Axis 1
• Questionnaires and interviews such as in the KimCohen study may find what they are looking for
CULTURAL ISSUES and the DSM
Culture does not affect diagnosis
Culture does affect diagnosis
• It’s scientific, and if we
clearly define our symptoms
then it can work all over the
world eg Lee(2006) in Korea
• Schizophrenia is more
similar across cultures than
different
• Some times symptoms mean
different things in different
cultures eg hearing voices can
make you “special” in a
positive way (spiritual)
• There are cultural differences
in symptoms
• Eg more auditory
hallucinations in Mexico, more
grandiosity in white
Americans,
Culture Bound Syndromes
• Genital retraction syndrome (Africa and Asia)
• Kuru (Papua New Guinea) brain disease
similar to mental illness here
What should we do about the cultural
problems in using the DSM?
•We should be aware of the cultural
problems in diagnosis
•Concentrate less on first rank
(positive) symptoms which tend to be
more cultural
•Concentrate more on negative
symptoms which are less culturebound and easier to measure
objectively