"Mental retardation" is an outdated term that is no longer used in clinical practice due to its negative connotations. The current and preferred term is Intellectual Disability (ID) or Intellectual Developmental Disorder.
Intellectual Disability is a neurodevelopmental disorder characterized by significant limitations in two main areas, with an onset during the developmental period (before the age of 18):
Limitations in Intellectual Functioning: This includes deficits in reasoning, problem-solving, planning, abstract thinking, judgment, academic learning, and learning from experience. It is typically assessed by standardized IQ tests, with a score of approximately 70 or below indicating a significant limitation.
Limitations in Adaptive Functioning: This involves deficits in skills needed for daily life. It is assessed across three domains:
Conceptual Skills: Language, reading, writing, math, reasoning.
Social Skills: Empathy, social judgment, communication skills, ability to make friends.
Practical Skills: Personal care, job responsibilities, money management, recreation.
The severity of Intellectual Disability (Mild, Moderate, Severe, Profound) is now determined by the level of impairment in adaptive functioning, not just the IQ score.