88b - Psychiatric Classification and Diagnosis

Question 1

The DMS shifted to polythetic criteria in DSM-___

What does this mean?

Answer 1

The DMS shifted to polythetic criteria in DSM- III

• Introduced “total number” and “cutoff number” of symptoms/criteria
• The DSM-III is also known as the “atheoretical” period
  
  • More description of symptoms
  • Less focus on meaning behind symptoms
    (@Freud was most likely unhappy)
  • allowed for the standardization of research
  • main goal of DSM3 was to improve reliability of psychiatric diagnosis and facilitate research on etiopathogenesis

Question 2

What is the difference between reliability and validity in psychiatric diagnosis?

Answer 2

• Reliability - about the consistency of the measure
  
  • Different clinicians come to the same diagnosis for the same patient
  • The same patient presenting at different times gets the same diagnosis
• Validity - about the accuracy of the measure
  
  • Face validity - does this test measure what it claims to measure
  • Descriptive validity - accuracy and objectivity of the info gathered
  • Predicted validity - can predict course, consequences of progression
  • Construct validity - sensitivity and specificity
  • Validity is hard to achieve in psychiatric diagnoses due to complexity of human behavior and cognition

Reliability is necessary but not sufficient for validity

Question 3

What is difference btwn categorical diagnosis and dimensional systems?

Answer 3

• Categorical diagnosis may be defined by a set of rules/criteria, a glossary of descriptions, or Yes/No answers
• Dimensional system uses ratings on a variety of dimensions or scales, often w/ normative comparisons and cutoff points (How often, how severe, how many, etc.)

Question 4

How was the DSM-4 organized?

Answer 4

• DSM4 system had 5 domains/axes:
  
  • Domain 1 clinical disorders (Ex. major depressive disorder)
  • Domain 2 personality disorders and mental retardation (Ex. borderline personality disorder)
  • Domain 3 general medical conditions (non-psychiatric) (Ex. hypothyroidism)
  • Domain 4 psychosocial and environmental stressors (ex. unemployment, conflict w/ partner)
  • Domain 5 global assessment of functioning

DSM5 got rid of this multiaxial system