Understanding DSM-5 Criteria for Diagnosing Intellectual Disability

Introduction

Intellectual disability (ID) is a neurodevelopmental disorder characterized by significant limitations in both intellectual functioning and adaptive behavior. The American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) outlines specific criteria for diagnosing ID. Understanding these criteria is essential for accurate assessment and intervention strategies.

Details

• Criterion A: Deficits in Intellectual Functioning

  • This involves impairments in reasoning, problem-solving, planning, abstract thinking, judgment, academic learning, and learning from experience.
    • Typically assessed through standardized tests, where an IQ score below 70 is indicative of intellectual disability.
    • A score significantly below the average range (usually defined as below 2 standard deviations from the norm) is required for consideration.

• Criterion B: Deficits in Adaptive Functioning

  • Refers to the difficulties in meeting developmental and sociocultural standards for personal independence and social responsibility.
    • Divided into three domains:
      • Conceptual Domain:
        • Involves academic abilities (reading, writing, math) and understanding complex concepts.
      • Social Domain:
        • Involves forming friendships, responding to social cues, and protecting oneself from risk.
      • Practical Domain:
        • Involves personal care, safety, using transportation, and managing daily tasks.

• Criterion C: Onset During Developmental Period

  • Intellectual and adaptive difficulties must manifest during the developmental period, which typically encompasses childhood and adolescence.
    • The age of onset is generally recognized as before the age of 18, distinguishing ID from other acquired cognitive impairments.

• Criterion D: Severity Levels

  • ID is categorized into levels of severity, which are defined based on adaptive behavior rather than solely IQ scores.
    • Mild ID:
      • IQ range of approximately 50-69; likely to achieve academic and self-care skills up to a 6th-grade level.
    • Moderate ID:
      • IQ range of approximately 35-49; may develop communication skills and self-care, but require support with daily tasks.
    • Severe ID:
      • IQ range of approximately 20-34; may communicate verbally and require significant support for daily living.
    • Profound ID:
      • IQ below 20; often require lifelong care and support, with limited communication abilities.

Conclusion

The DSM-5 outlines critical criteria for diagnosing intellectual disability that includes deficits in intellectual and adaptive functioning, onset during the developmental period, and consideration of severity levels. Understanding and applying these criteria is essential for healthcare professionals to provide appropriate diagnosis and support tailored to individuals with ID.