The DSM – how valid and reliable is it as a tool

for diagnosis?

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DSM – a multi-axial system

• Axis I 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

validityWeaknesses• 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 Kim-Cohen study may find what they are looking for

CULTURAL ISSUES and the DSM

Culture does not 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

Culture does affect diagnosis• 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 culture-bound and easier to measure objectively