1. Chapter 3 Classification and Diagnosis
Introduction to Clinical Psychology 2e hunsley & lee
PREPARED BY DR. cathy chovaz, king’s college, Uwo

2. Introduction – Topics Important Aspects of a Classification Scheme
Defining Abnormal Behaviour
Diagnosis and Defining Disorder
The Development of a Disorder
The DSM Approach to Diagnosis: History
The DSM Approach to Diagnosis
The DSM Approach to Diagnosis Problems/Limitations
Other Classification Schemes

3. Important Aspects of a Classification Scheme
Classification: a way for scientists to organize, describe, and relate the subject matter of their discipline
Validity: whether a classification scheme is accurately capturing reality
Utility: how useful a classification scheme is
Diagnosis system: a classification based on rules used to organize and understand diseases and disorders

4. Important Aspects of a Classification Scheme
Categorical approach: an object is determined to be a member of a category or not (e.g., depressed or not depressed)
Dimensional approach: an object differs in degree from others – a continuum (e.g., mildly depressed, moderately depressed, severely depressed)
Prototype model: members of a category may differ in degree to which they represent a common example (used in DSM)

5. Defining Abnormal Behaviour
What is abnormal? Many factors need to be considered including:
The cultural and societal context
Whether there is distress or discomfort
Whether the problem is harming others
How common the problem is
How much it is interfering with a person’s ability to function
If it is common for that person’s developmental stage (developmental psychopathology)

6. Diagnosis and Defining Disorder
No diagnosis is based on a single symptom
DSM-IV-TR defines disorder in a complicated fashion including
Symptoms associated with distress or impairment/disability
Increased risk of suffering
Culturally atypical
Not just deviant behaviour (unless there is also dysfunction)

7. Diagnosis and Defining Disorder
Wakefield – Harmful Dysfunction: the problem must be clear and there must be harm to person or others
Dyscontrol: impairment must be involuntary or not readily controlled

8. The Development of Disorders
Most all contemporary models are biopsychosocial – but different theories represent different emphases
Some models emphasize biological aspects while others emphasize psychological or social aspects
Life stress model – important impact of the number of life stressors on the development of disorders

9. The DSM Approach to Diagnosis: History
First edition of DSM (1952) had fairly vague terms and emphasized psychodynamic contributions
DSM-II (1968) was less psychodynamically focused as medications were more commonly being used
DSM-III (1980) guided by Robert Spitzer, was atheoretical (revision done in 1987)
Focus on diagnostic criteria, multiaxial, increase in focus on reliability

10. The DSM Approach to Diagnosis: History
DSM-IV (1994)
Further focus on reliability
‘Work groups’ worked on clusters of disorders
Text revision (diagnostic criteria unchanged) DSM-IV’TR’ completed in 2000
DSM-V planned for 2012

11. The DSM Approach to Diagnosis: History
The DSM-IV uses a multiaxial classification approach. Axis I and II are the mental disorders and III-V provide the medical and psychosocial contexts

12. The DSM Approach to Diagnosis
Axis I: Clinical Disorders and Other Conditions That May Be a Focus of Clinical Attention
All the mental disorders in the DSM-IV except for Personality Disorders and Mental Retardation. Multiple disorders can exist on Axis I
Axis II: Personality Disorder and Mental Retardation
These were placed on another axis so that they were not overlooked

13. The DSM Approach to Diagnosis
Axis III: General Medical Conditions
Current medical conditions that may be relevant to the understanding or treatment of Axis I or II
Axis IV: Psychosocial/Environmental Problems
Psychosocial and environmental information that may influence the diagnosis, treatment, and prognosis of Axis I or II, including educational, economic, housing, legal problems, etc.
Axis V: Global Assessment of Functioning
Score of indicating their functioning level

14. The DSM Approach to Diagnosis
Importance of considering culture
Information in the text on cultural variation
Cultural bound syndromes
Diagnosis should not occur if symptoms are culturally typical
Diagnosis must be done in a culturally sensitive context

15. The DSM Approach to Diagnosis Problems/Limitations
Comorbidity: when a person receives two diagnoses at once
DSM attempts to decrease the likelihood of this with several exclusionary rules
However, comorbidity is very common in the DSM (often >40%)
Diagnoses do not account for normal reactions to life stressors (e.g., divorce, terminal illness)

16. The DSM Approach to Diagnosis Problems/Limitations
Diagnostic criteria seem to include too much of the population (sometimes 25-30% of the population)
Although better than the earlier versions DSM diagnoses are not as reliable as hoped
Heterogeneity of symptom profiles is problematic
Many of the subtypes and features of a disorder are not based on empirical data

17. The DSM Approach to Diagnosis Problems/Limitations
Validity of some disorders is questionable (i.e., that the diagnosis is a discrete entity)
Current research indicates that some disorders may be both a category and a continuum (e.g., depression)
Resilience is often not included in understanding disorders, yet is a common aspect of human functioning

18. Other Classification Schemes
International Statistical Classification of Diseases and Related Health Problems (ICD-10) – developed by World Health Org.
Mental and behavioural disorders subsection (compatible with the DSM-IV)
Companion “International Classification of Functioning, Disability and Health (ICF)” focused on overall functioning and health
Achenbach System of Empirically Based Assessment
(ASEBA)– internalizing/externalizing problems

19. Copyright
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