Classification systems DSM

Question 1

What is the DSM?
(Diagnostic and statistical manual)

Answer 1

-Describes and classifies symptoms, features and associated risk factors of over 300 mental and behavioural disorders used throughout the US and in many nations across the world.
-arguably this is an important first step on the journey to support and treatment.

Question 2

The DSM-V/ DSM-5
(most recent edition in 2013 with three sections).

section one
guidance

section two
details
examines symptoms

section three
suggestions
includes info about..

Answer 2

Section one
-guidance about using the new system.

Section two
-details of disorders, categorised according to current understanding of underlying causes and similarities between symptoms.
-examines symptoms of some disorders differently from previous editions, e.g the five subtypes of schizophrenia have been removed and a dimensional assessment added.

Section three
-suggestions for new disorders (e.g internet gaming disorder) that should have further investigation.
-includes information about impact of culture on presentation of symptoms and how symptoms are communicated (especially when the clinician is from a different cultural background).

Question 3

Making the diagnosis using the DSM

what’s it generally based on?

what does the diagnosis often involve?

what’s a problem with difficult cases?

Answer 3

-Generally based on unstructured (clinical) interviews but many structured interview schedules are also available, based on symptom lists. (e.g BDI)
-Diagnosis often involves ruling out disorders which do not match the persons symptoms sufficiently.
-Uncomplicated problems may take a GP ten minutes to diagnose. Difficult cases may take weeks or months in order to understand the consistency of symptoms overtime.

Question 4

Reliability

Answer 4

consistency of diagnosis

Question 5

validity

Answer 5

whether a real disorder has been diagnosed.

Question 6

How reliability and validity are assessed

what’s Cohens Kappa?

Answer 6

-Reliability of the DSM-III checked using Cohens kappa = proportion of people who get the same diagnosis when assessed then re-assessed, either at a later time (test-retest reliability) or by an alternative practitioner (inter-rater reliability). 0.7 is ‘good agreement’ (Spitzer et al. 2012).

-several types of validity are relevant to diagnosis
descriptive
aetiological
concurrent
predictive

Question 7

what are the types of validity (4)

Answer 7

descriptive
aetiological
concurrent
predictive

Question 8

Descriptive validity

Answer 8

two people with the same diagnosis exhibit similar symptoms.

Question 9

aetiological validity

Answer 9

two people with the same diagnosis share similar casual factors

Question 10

concurrent validity

Answer 10

a clinician uses more than one method or technique to reach the same diagnosis.

Question 11

predictive validity

Answer 11

accurately predicting outcomes for an individual from their diagnosis (e.g prognosis).

Question 12

Reliability of the DSM
Strength

what’s good about field trials?

what did relier et al 2013 show? (kappa values)

why is this important?

Answer 12

-The DSM-5 is a good level of agreement for some disorders.
-Field trials demonstrated impressive agreement between clinicians for a variety of disorders.
-Three disorders (e.g PTSD) had kappa values of 0.60-0.79 (very good). Seven more disorders (e.g schizophrenia) had values of 0.40-0.59 (good, relier et al. 2013).
-This is important because the criteria for PTSD have changed (e.g specific symptoms for a diagnosis) and clinicians have clearly adapted well.

Question 13

Reliability of the DSM
Weakness

What’s an issue associated with standards?

what did Cooper 2014 classify as acceptable?

what was one of the least reliable diagnoses by relier et al 2013?

Answer 13

-weakness of the DSM-5 is the issue of falling standards.
-The ‘acceptable level of agreement has fallen over the last 35 years.
-0.2-0.4 was classified as ‘acceptable’ (Cooper 2014). Major depressive disorder was one of the least reliable diagnoses (0.28, relier et al. 2013).
-This suggests the DSM-5 may be less reliable than previous versions (e.g diagnoses of MDD may have been mistaken, with other cases missed.

Question 14

who showed that Three disorders (e.g PTSD) had kappa values of 0.60-0.79 (very good). Seven more disorders (e.g schizophrenia) had values of 0.40-0.59 (good).
Major depressive disorder was one of the least reliable diagnoses (0.28)

Answer 14

relier et al 2013

Question 15

who classified 0.2-0.4 as acceptable

Answer 15

Cooper 2014

Question 16

counter argument for reliability

what were clinicians in the DSM-5 trails asked?
what did the DSM-II use in contrast?
who suggested this?

Answer 16

However
clinicians in the DSM-5 field trials were asked to ‘work as they usually would’ (e.g take clients as they come), to mirror normal practice. In contrast, the DSM-III used carefully screened ‘test’ clients, and clinicians had detailed training.
So it is no surprise that DSM-5 trials had lower reliability (Kupfer and Kraemer 2012).

Question 17

Validity of the DSM
Strength

what did Kim-cohen et al 2005 show?
Aetiological validity
predictive validity

Answer 17

-strength of the DSM is support for the validity of conduct disorder (CD)
Kim-Cohen et al. (2005) showed validity for CD.
-for concurrent, interviews of children and mothers, observation of anti-social behaviour, questionnaire with teachers.
Aetiological found the risk factors were common (e.g male, low income).
Predictive found that 5 year olds with CD more likely to have behavioural problems at 7.
-This is a strength as accurate diagnosis helps reduce adult mental health problems preceded by symptoms of CD.

Question 18

Validity of the DSM
Weakness

what’s a problem with labels?
how does this not help with disorder info?

Answer 18

-labels tell us nothing about the causes
-Mererly naming or classifying a disorder does not actually tell us anything about its causes.
-Circular logic, why does someone hear voices? They had schizophrenia. How do we know they have schizophrenia? They hear voices.
-The result of a diagnosis is simply a label and tells us nothing useful.