Chapter 4
Classification and Diagnosis
Classification
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Helps to more clearly define problems
Provides basis for communication
Necessary for research and advancing
scientific understandings
First step to deciding on treatment
DSM classification
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Diagnostic and Statistical Manual (DSM) of the
American Psychiatric Association
First DSM published in 1952
DSM-III (1980) introduced multi-axial classifications
DSM-IV (1994) Dr. Allen Frances chaired the
working group task force
DSM-5 (2013) introduces changes including
elimination of multi-axial system
DSM-5 Development
Goals for DSM-5:
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Address gaps in diagnoses
Update criteria based on new research knowledge
Reduce the number of Not Otherwise Specified
(NOS) classifications because too generic
Add dimensions to categorical system
Streamline and simplify diagnoses
Overview of DSM-5 changes
1. New disorders (e.g., binge eating disorder)
2. New criteria for some existing disorders
3. Combining some disorders into a single bigger category
4. New conceptualizations for current disorders (e.g.,
OCD is no longer considered an anxiety disorder)
5. New names for some existing disorders
6. New dimensional ratings within some disorders
7. Suicidal risk now highlighted
8. Reorganization of age-related considerations
DSM-5 Controversies
1. Autism Spectrum Disorder – eliminates previous
Asperger’s syndrome diagnosis
2. Disruptive Mood Dysregulation Disorder is
criticized as “temper tantrum disorder”
3. Bereavement can no longer exclude Major
Depression – may over-diagnose normal grieving
4. Personality disorders still classified as categories
not dimensions
5. Some disorders being considered were omitted
(non-suicidal self-injury)
DSM-5 Controversies (cont.)
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Dr. Allen Frances argues:
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that DSM-5 changes will lead to dramatic increase in
number of people diagnosed with disorders termed
diagnostic inflation
that the pharmaceutical industry will benefit most by
developing new drugs for new disorders and new
people qualifying for reimbursement since they are
now diagnosed
for a return to a more cautious approach to diagnostic
classification
Key Concepts in Classification
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Epidemiology – study of frequency of disorders in
populations
Prevalence – proportion of people who have a
diagnosis at any given time
Lifetime prevalence – proportion who have ever had
a diagnosis in their lifetime
When prevalence rates rise dramatically, there is
concern that ‘normal’ individuals are being
incorrectly diagnosed
Key concepts in classification (cont.)
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Comorbidity
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defined as the co-occurrence of different
disorders
considered a major issue because it makes
treatment planning more difficult
when there is high co-morbidity it raises
concerns that the disorder is not distinct
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Overview of DSM-5 Diagnostic
Categories
Neurodevelopmental Disorders
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ADHD
Intellectual Disability
Autism Spectrum Disorders
Communication Disorders
Neurocognitive Disorders
Substance-Related and Addictive
Disorders
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Substance-related disorder
Gambling disorder
Schizophrenia Spectrum and Other
Psychotic Disorders
Depressive Disorders
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Major depressive disorder
Mania
Bipolar disorder
Premenstrual dysphoric disorder
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Anxiety Disorders
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Specific Phobia
Panic disorder
Generalized anxiety
disorder
Separation anxiety
disorder
Obsessive
Compulsive and
Related Disorders
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Obsessivecompulsive disorder
Body dysmorphic
disorder
Trichotillomania
Hoarding Disorder
Overview of DSM-5 Diagnostic
Categories (cont.)
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Somatic Symptom and
Related Disorders
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Somatic symptom disorder
Conversion disorder
Illness Anxiety Disorder
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Dissociative Disorders
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Dissociative amnesia
Dissociative identity
disorder
Depersonalization/derealizat
ion disorder
Sexual Dysfunctions
Paraphilic Disorders
Sleep-Wake Disorders
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Insomnia and Dyssomnia
Parasomnias
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Feeding and Eating Disorders
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Anorexia nervosa
Bulimia nervosa
Binge eating disorder
Trauma and Trauma related
Disorders
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PTSD
Acute stress disorder
Adjustment disorders
Disruptive, Impulse-Control
and Conduct Disorders
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Intermittent explosive disorder
Kleptomania
Pyromania
Oppositional Defiant Disorder
Conduct Disorder
Overview of DSM-5 Diagnostic
Categories (cont.)
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Personality Disorders
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Schizoid personality disorder
Narcissistic personality disorder
Anti-social personality disorder, etc.
Personality Disorders were previously categorized
on Axis II (DSM-IV-TR)
Criticisms of Classification
• General Criticisms
• Loss of information about person
• Stigmatizing
• Specific Criticisms
• Discrete Entity vs. Continuum
• Dimensional Classification vs.
Categorical Classification
• DSM represents a categorical
classification
• Yes–No approach to classification
• Continuity between normal and
abnormal behaviour not taken into
consideration
Advantages of categorical versus
dimensional classification
Categorical
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if need to know if
person either has
does not have
disorder
if need to know
whether to start or
not start certain
treatment
Dimensional
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most helpful when
the disorder has
levels (from mild to
severe)
tends to have less
comorbidity since
measures are on a
continuum, not all or
none
Reliability
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Reliability is the cornerstone of any diagnostic
system
Measures consistency
Inter-rater reliability
Components of reliability
• Sensitivity
• Extent to which there is agreement that the diagnosis is
detected as being present
• Specificity
• Extent to which there is agreement that the diagnosis is
absent
• Kappa
• Statistic used to measure extent of agreement over and
above chance levels
Improvements in Reliability
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Early editions of the
DSM (prior to DSMIII)
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were unreliable
many diagnostic
disagreements
Information provided
to make diagnoses
depended on what
an individual
clinician might
choose to ask about
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Newer editions of
DSM
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more extensive
descriptions
more precise
diagnostic criteria
increased use of
standardized
diagnostic interviews
has improved
reliability by
providing same
detailed information
Validity
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Construct validity is most important for diagnosis
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How well does the diagnosis relate to other aspects of the
disorder?
Culture and Diagnosis
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Early editions of DSM were criticized for lack of
consideration of culture and ethnicity
DSM-IV-TR introduced culture-bound
syndromes:
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amok – dissociative episode involving a period of
brooding followed by violent outburst
DSM-5 elaborated four specific themes to be
considered in making cultural formulation:
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Cultural identity
Cultural consideration of distress
Cultural features of vulnerability and resilience
Cultural features of the relationship between
clinician and patient
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